12 2021 2 AnnaleSKinesiologiae UDK / UDC 796.01:612 | Annales Kinesiologiae 12, 2021, 2, pp. 71–148 | ISSN 2232-2620 8, 2017, 1 A nnaleSK inesiologiae AnnaleSKinesiologiae UDK / UDC 796.01:612 | Annales Kinesiologiae 8, 2017, 1, pp. 1–64 | ISSN 2232-2620 AnnaleSKinesiologiae UDK / UDC 796.01:612 | Annales Kinesiologiae 12, 2021, 2, pp. 71–148 | ISSN 2232-2620 Koper 2021 ISSN 2232-2620 UDK/UDC 796.01:612 Volume 12, Year 2021, Number 2 ISSN (online ed.) 2335-4240 Editor in Chief / Glavni in odgovorni urednik: Rado Pišot Editors / Uredniki: Peter Čerče, Petra Dolenc, Mitja Gerževič, Mihaela Jurdana, Uroš Marušič, Cecil J. W. Meulenberg, Nina Mohorko, Armin Paravlić, Saša Pišot, Matej Plevnik, Boštjan Šimunič Editorial Board / Uredniški odbor: Guglielmo Antonutto (Ita), Bojan Borštner (Slo), Andrej Čretnik (Slo), Natale Gaspare de Santo (Ita), Pietro di Prampero (Ita), Nandu Goswami (Aut), Jay R. Hoffman (USA), Aleš Holobar (Slo), Peter Kokol (Slo), Stefano Lazzer (Ita), Zlatko Matjačić (Slo), Zoran Milanović (Srb), Jurij Planinšec (Slo), Carlo Reggiani (Ita), Vesna Štemberger (Slo), Matjaž Vogrin (Slo), Jernej Završnik (Slo), Milan Žvan (Slo) Language Editors / Lektorji: Rick Harsch, Jezikovna zadruga Soglasnik (en.), Nina Novak, Polona Šergon (sl.) Translation / Prevod: Petra Berlot Kužner (en./sl.) Graphic Design of the Cover / Oblikovanje naslovnice: Mateja Oblak Typesetting / Stavek: Alenka Obid Publisher / Izdajatelj: Science and Research Centre Koper, Annales ZRS / Znanstveno-raziskovalno središče Koper, Annales ZRS Journal secretary contact / Sedež: Annales Kinesiologiae, Science and Research Centre Koper, Garibaldijeva 1, SI-6000 Koper/Capodistria tel.: +386 5 663-77-00; fax: +386 5 663-77-10 E-mail: annaleskin@zrs-kp.si Home page: http://ojs.zrs-kp.si/index.php/AK Printing / Tisk: Grafika 3000 d.o.o. Quantity / Naklada: 250 copies per issue Financial support / Finančna podpora: The publishing of this journal is supported by the Slovenian Research Agency. Izdajo revije sofinancira Javna agencija za raziskovalno dejavnost Republike Slovenije. Journal abbreviation: Ann. Kinesiol. Annales Kinesiologiae is an international journal published twice a year. Annual subscriptions (2 issues in English language) are available for 25 eur, and a single issue is available for 15 eur. For students 20% discount applies upon presenting an international valid student ID. Subscription requests can be send to: annaleskin@zrs-kp.si TABLE OF CONTENTS Saša Pišot: ............................................................................................................... Editorial Uvodnik Kaja Stanković, Nejka Potočnik: ........................................................................... The Effect of Phonated Breathing on Oxygen Uptake During and After Submaximal Cycling Vpliv dihalnega vzorca na ventilacijo in privzem kisika med in po submaksimalni vadbi na sobnem kolesu Carlo Rossi, Roberto Roklicer, Antonino Bianco, Marko Manojlovic, Barbara Gilic, Tatjana Trivic, Patrik Drid: .......................................................... The Effect of Rapid Weight Loss on the Handgrip Strength of National-Level Wrestlers Učinki naglega zmanjševanja telesne mase na moč oprijema pri reprezentančnih rokoborcih Stojan Puhalj, Blaž Lešnik, Alexander Povhe, Robi Kelc, Črtomir Matejek: .................................................................................................... Correlations Between Motor and Anthropometric Variables and the Performance of Young Competitors in Alpine Skiing Povezanost antropometričnih in motoričnih spremenljivk z uspešnostjo mlajših dečkov v alpskem smučanju Saša Pišot, Rado Pišot, Boštjan Šimunič: .............................................................. Time Passes – Healthy Habits Stay? A Longitudinal Small Sample Comparison of Muscle Contractile Properties, Motor Abilities and Lifestyle Characteristics of Athletes and Non-athletes Čas mineva - zdrave navade ostanejo? Longitudinalna primerjava kontraktilnih lastnosti mišic, gibalnih sposobnosti in značilnosti življenjskega sloga športnikov in nešportnikov na majhnem vzorcu REVIEWS AND REPORTS OCENE IN POROČILA Saša Pišot, Kaja Teraž: ........................................................................................... 11th International Scientific and Professional Conference “A Child in Motion” 11. Mednarodna znanstvena in strokovna konferenca Otrok v gibanju 71 73 91 103 117 137 Boštjan Šimunič: ..................................................................................................... Workshop Report: Physical Activity-Related Injuries Prevention in Adolescents. What Do We Know? Poročilo delavnice: Physical Activity-Related Injuries Prevention in Adolescents. What Do We Know? Guidelines for authors .............................................................................................. Navodila avtorjem 141 145 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 71 EDITORIAL This issue is again marked by the impact of the COVID-19 pandemic and the re- lated restrictive measures, which is why the authors examine the possibility of curative exercise with aids that can ease the effort of exercise, especially for lung patients. Un- fortunately, research often does not provide immediate answers and it takes time, new measurement protocols, new subjects, etc. to translate scientific findings into practice. It is this new, unexpected experience with the coronavirus disease that continues to raise new questions in all fields. Due to its preventive, rehabilitative and curative as- pects, kinesiology is one of the applied sciences, alongside medicine, that needs to find answers as quickly as possible. Competitive sport is also no exception. The knowledge that certain physiological parameters of the athlete can be influenced by non-invasive procedures, personalised training and specific dietary regimes is very useful for coaches and athletes. In this journal, the authors discuss how body mass manipulation and a specific high-intensity training routine in wrestling can influence grip strength, and how certain anthropomet- ric and motor parameters are related to the competitive performance of young alpine skiers. As an aid to training routines and general monitoring of an athlete’s develop- ment, applied knowledge once again demonstrates that it can significantly contribute to peak performance, in addition to talent and external factors. That knowledge becomes latent in one’s own behaviour and that habits of an active and healthy lifestyle remain lifelong companions if they are introduced early enough in the form of regular and organised physical/sporting activity in childhood is the finding of a longitudinal study that concludes the scientific contributions of this issue. We are also pleased to present some of the activities of the Institute for Kinesiology Research of the Science and Research Centre Koper. The live workshop on sports inju- ries in young athletes and the international scientific and specialist conference Child in Motion, which both saw a high attendance, confirm their relevance in the professional and scientific arena. In conclusion, we pledge to continue our efforts in future editions to pursue the journal’s mission and to present answers to current issues. Clearly, the impact of the pandemic will continue to accompany and fuel research momentum, and the need to raise awareness of the syndemic effects of the COVID-19 pandemic among the pro- fessional community is already becoming apparent. The effects of the pandemic will continue to be present in all aspects of our lives for quite some time, and kinesiologists and experts in related disciplines will continue to be forced to play an important role in the “battle” to stay healthy. Saša Pišot, PhD, Editor 72 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 UVODNIK Tudi tokratno številko zaznamujejo izkušnje omejitvenih ukrepov in posledic pan- demije covida-19, zato se avtorji sprašujejo o mogoči kurativni vadbi s pripomočki, ki bi predvsem pljučnim bolnikom olajšali napor pri vadbi. Raziskave žal velikokrat ne prinašajo takojšnih odgovorov in potreben je dodaten čas, nov merski protokol, novi subjekti ipd., da se znanstveni izsledki lahko prenesejo v prakso. Prav ta nova, nepri- čakovana izkušnja s koronavirusno boleznijo še vedno odpira nova vprašanja na vseh področjih. Kineziologija je zaradi svojega zdravstvenega preventivnega, rehabilitacij- skega in kurativnega vidika poleg medicine med tistimi uporabnimi vedami, ki morajo kar najhitreje poiskati odgovore. Tudi vrhunski šport ni izjema. Zavedanje, da je na določene fiziološke parametre športnika mogoče vplivati z neinvazivnimi posegi, prilagojeno vadbo in določenimi prehranskimi režimi, je dobrodošla podpora trenerjem in športnikom. Kako lahko ma- nipulacija telesne mase in poseben visoko intenziven vadbeni režim pri rokoborcih vplivata na moč stiska ter kako so določeni antropometrični in motorični parametri po- vezani s tekmovalno uspešnostjo mlajših alpskih smučarjev, odkrivajo avtorji v reviji, ki je pred vami. Uporabno znanje kot pripomoček pri vadbenih režimih in splošnem spremljanju športnikovega razvoja ponovno kaže, da lahko poleg talenta in zunanjih dejavnikov pomembno prispeva k vrhunskemu rezultatu. Da postane znanje latentno v lastnem vedênju, da navade aktivnega in zdravega ži- vljenjskega sloga ostanejo vseživljenjske spremljevalke, če so »sprožene« dovolj zgo- daj v obliki redne in organizirane gibalne/športne aktivnosti v otroštvu, je ugotovljeno v longitudinalni raziskavi, ki končuje znanstvene prispevke te številke. Veseli nas, da lahko predstavimo tudi nekaj dejavnosti Inštituta za kineziološke raz- iskave ZRS Koper. V živo izpeljani delavnici o športnih poškodbah mladih športnikov ter mednarodni znanstveni in strokovni konferenci Otrok v gibanju, obe z zavidljivim odzivom, potrjujeta svojo pomembnost v strokovnem in znanstvenem prostoru. Ob koncu še zaveza, da si bomo tudi v prihodnjih letnikih prizadevali slediti ciljem poslanstva revije in predstavljali odgovore na aktualne probleme. Očitno bodo izku- šnje in posledice pandemije še naprej spremljevalke in vzvod za dodaten raziskovalni zagon, ob tem pa se že kaže nuja po ozaveščanju strokovne javnosti o t. i. sindemičnih učinkih pandemije covida-19. Ti bodo še lep čas prisotni na vseh področjih našega življenja, strokovnjaki kineziologije in sorodnih ved pa bodo še naprej prisiljeni imeti pomembno vlogo v »boju« za ohranjanje zdravja. Dr. Saša Pišot, urednica ANNALES KINESIOLOGIAE • 12 • 2021 • 2 73 THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE DURING AND AFTER SUBMAXIMAL CYCLING Kaja STANKOVIĆ1, Nejka POTOČNIK1 1Institute of Physiology, Medical Faculty, University of Ljubljana, Slovenia Corresponding author: Nejka POTOČNIK University of Ljubljana, Medical Faculty, Institute of Physiology, Zaloška 4, 1000 Ljubljana, Slovenia Phone: +386 1 543 7523 E-mail: nejka.potocnik@mf.uni-lj.si ABSTRACT Purpose: Positive expiratory pressure (PEP) exhalation during exercise is reported to improve body adaptation to exercise and enhance the exercise tolerance in patients with chronic obstructive pulmonary disease. Wearing mouthguards results in lower oxygen consumption and increased performance by increasing PEP in athletes. Airway resistance during expiration can be manipulated by phonation. Thus, the aim of our study was to examine the effects of phonated breathing on cardiopulmonary adaptation to moderate exercise and subsequent recovery. Methods: 26 young healthy participants conducted the same moderate stea- dy cycling protocol using three different breathing patterns: spontaneous breathing (BrP1), phonated breathing pronouncing the sound “h” (BrP2) and phonated breathing pronouncing the sound “sh” (BrP3). Heart rate, oxygen consumption, CO2 production, respiratory rate, tidal volume, respiratory exchange ratio and ventilatory equivalents were measured (Cosmed, Italy) before, during and 20 minutes after cycling. Data were analyzed using SPSS, with significance level p<0.05. Results: The analysis revealed no significant differences related to the breathing economy; respiratory rate was increased, and tidal volume decreased with spontaneous breathing compared to both phonated breathing patterns during exercise; no effect of BrPs on cardiopulmonary parameters was found in recovery. Conclusion: Our results do not confirm the assumption that PEP breathing improves exercise economy probably because of the low exercise intensity applied. Further studies should be conducted at higher exercise loads or in patients with pulmonary dysfunction. Keywords: phonated exhalation, breathing pattern, positive expiratory pressure, metabolic efficiency, moderate exercise Original scientific article DOI: https://doi.org/10.35469/ak.2021.329 received: 2022-07-05 UDC: 612.2:796.01 74 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 VPLIV DIHALNEGA VZORCA NA VENTILACIJO IN PRIVZEM KISIKA MED IN PO SUBMAKSIMALNI VADBI NA SOBNEM KOLESU IZVLEČEK Cilj: Izdih s pozitivnim tlakom (PEP) izboljša zmožnost fiziološke prilagoditve na napor ter vadbeno toleranco pri bolnikih s kronično obstruktivno pljučno boleznijo. Nošenje ustnih varoval, ki prav tako povečale upor v dihalnih poteh, zmanjša porabo kisika in poveča zmogljivost športnikov. Upor v dihalnih poteh lahko spreminjamo s fo- nacijo. Tako je namen naše raziskave ugotoviti, ali fonacija med zmerno telesno vadbo vpliva na spremembe srčnih in dihalnih parametrov med in po taki vadbi Metode: 26 mladih prostovoljcev je trikrat izvedlo enako zmerno kolesarjenje, vsa- kič ob uporabili drugačnega dihalnega vzorca (DV): spontano dihanje (DV1) in izdih ob izgovarjanju glasu H (DV2) oziroma Š (DV3). Pred, med in 20 minut po vadbi smo merili srčno frekvenco, porabo kisika, izločanje ogljikovega dioksida, frekvenco in vo- lumen dihanja, pljučno ventilacijo, respiratorni količnik in ventilacijske ekvivalente z metabometrom Cosmed. Podatke smo obdelali s programom SPSS in postavili mejo signifikantnosti pri p<0,05. Rezultati: Analiza rezultatov ni pokazala nobenih statistično značilnih sprememb metabolnih parametrov, kakor tudi ne srčne frekvence z ozirom na uporabljen DV. Zna- čilno povečana je bila le frekvenca dihanja in zmanjšan dihalni volumen pri spontanem dihanju glede na oba s fonacijo povezana DV med naporom. V okrevanju po naporu ni bilo nobenih razlik v merjenih parametrih. Zaključek: Rezultati naše študije niso potrdili domneve, da dihanje s PEP, ki ga povzročimo s fonacijo, poveča učinkovitost telesne vadbe, zmanjša porabo kisika in iz- boljša telesno zmogljivost vendar ocenjujemo, da je bila intenziteta vadbe v naši študiji premajhna, da bi se tovrstne razlike izkazale. Zato bi bilo treba opraviti še nadaljnje raziskave in sicer z večjo obremenitvijo pri zdravih preiskovancih ali pa na bolnikih z respiratorno motnjo. Ključne besede: fonacija, dihalni vzorec, pozitivni tlak v dihalnih poteh med izdi- hom, metabolna učinkovitost, zmerna vadba 75 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 INTRODUCTION Breathing patterns (BrP) differ according to breathing frequency, breathing depth, inhalation/exhalation time relationship, and maneuvers applied during expiration (Dal- lam & Kies, 2020). Expiratory maneuvers are particularly important since changing the resistance of the airways upon expiration can help maintain a positive pressure until the end of exhalation, thus keeping the alveoli and airways open (Francis & Brasher, 1991) longer during the exhalation period. Phonation requires sustained/controlled ex- halation. During speech and singing, breath duration and flow rates are controlled to support sound generation by the larynx (Lewis et al., 2021). Regulation of the glottic aperture by laryngeal muscle activity also helps to control ventilation (Lewis et al., 2021). Therefore, the larynx could be considered a key modulator of expiratory flow upon phonation. Pronunciation of different voices can be used to change the resistance in the airways during exhalation (Hoffmann, Torregrosa, & Bardy, 2012). Grunting has been shown to improve force production during exercise (O'Connell et al., 2016). In elite sports, there is a continuous search for strategies to improve performance (Harbour, Stöggl, Schwameder, & Finkenzeller, 2022). On the other hand, in patients with compromised breathing, strategies to minimize breathing effort during exercise would be appreciated to allow these patients to minimize the exercise associated dis- comfort (Fagevik Olsén, Lannefors, & Westerdahl, 2015). The way we breathe strongly affects not only the respiratory system itself but also other systems in our body: car- diovascular, nervous, endocrine, lymphatic, immune, digestive (Saoji, Raghavendra, Madle, & Manjunath, 2018). To manipulate exhalation, pursed lip breathing (Tiep, Burns, Kao, Madison, & Her- rera, 1986), specially designed mouthguards (Lässing et al., 2021) or simply phonati- on of some particular voices could be applied during exercise to increase the airways resistance during exhalation. By breathing out against increased resistance, positive expiratory pressure (PEP) is achieved and it is commonly believed that PEP improves ventilation, at least in patients with pulmonary diseases (Fagevik Olsén & Westerdahl, 2009; Fagevik Olsén , Lannefors, & Westerdahl, 2015), and potentially during exercise (Phimphasak, Ubolsakka-Jones, & Jones, 2018). There are only a few studies about the effects of BrP on the physiological respon- se to exercise (Green, Benson, & Martin, 2018; Lässing et al., 2021). Our recent study (Klanjšček, 2018) found that BrPs with increased expiratory resistance had a significant favorable effect on the economy of short-lasting trunk stabilization exer- cise. Expiratory resistance was manipulated by pronouncing different sounds during exercise (Klanjšček, 2018) ‒ sound “sh” (as in push to increase resistance, and “h” (as in host) to decrease it ‒ and compared to spontaneous breathing. Oxygen con- sumption and carbon dioxide production decreased during short-lasting trunk stabi- lization exercise in the “sh” breathing pattern compared to the “h” breathing pattern and spontaneous breathing. Additionally, the respiratory quotient, ventilation, and heart rate during exercise decreased while ventilatory equivalents increased in the “sh” pattern compared to the “h” pattern and spontaneous breathing. The participants 76 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 perceived the “sh” pattern to be significantly easier compared to the other two BrPs (Klanjšček, 2018). Thus, we aimed to test whether the BrP where exhalation is manipulated by prono- uncing different sounds during exercise affects the physiological response to aerobic exercise. To this purpose, the heart rate, oxygen consumption, CO2 production, and ventilation were measured before, during and after moderate cycling at constant load using the three different BrPs: the pronunciation of “sh” or “h” during exhalation, and spontaneous breathing. Crossover design was used to avoid differences between parti- cipants. METHODS The study was performed in the Exercise Physiology Laboratory of the Institute of Physiology, Medical Faculty, University of Ljubljana. Ethical approval of the study was obtained from the National Ethics Committee (No. 0102-326 / 2018/5). Subjects 26 healthy participants with comparable levels of physical activity were recruited by public invitation to participate voluntarily in this crossover study. Their physical exami- nation and histories revealed no autonomic dysfunction, chronic diseases, medication usage or smoking. Their ECG and arterial blood pressure values were normal. Written informed consent was obtained before participation. The trial included 18 women and 8 men, 20.85 ± 0.2 years old, with body mass index (BMI) 22.97 ± 0.59 kg/m2. Experimental procedure The study was carried out in a climate controlled laboratory room between 9 and 12 am. The participants refrained from physical exertion for at least 1 day before the first exercise test and were asked not to perform additional physical activities during the experiment period. They were not allowed to consume any alcohol, caffeine or tobacco for at least 2 hours before the beginning of each exercise test and were asked to eat a light meal 1 hour before coming to the laboratory. Each participant visited the labo- ratory 3 times in February and March with at least one relaxing day between the two consecutive visits. During the three visits, participants performed the same submaximal aerobic cycling with different BrPs during exercise. The BrP applied during a particular visit was chosen randomly and marked BrP1 for spontaneous breathing and BrP2/BrP3 for exhaling upon pronouncing “h”/“sh”, respectively. Each session started with blood pressure measurement at sitting rest and an expla- nation of the breathing technique for the selected BrP. A silicone breathing mask was 77 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 placed upon the mouth and nose (Quark, Cosmed, Italy) to measure oxygen consump- tion, CO2 production, and ventilation; ECG electrodes and a finger cuff for continuous blood pressure tracing were attached (Finapres 2300, Ohmeda, USA). The measure- ment consisted of 5 minutes sitting at rest on a cycloergometer Ergoselect 100 (Ergo- line, Germany) (baseline), 5 minutes of cycling at 100 W (women) and 140 W (men), respectively, at a cadence of 60 rpm and followed by 10 minutes of passive recovery. During cycling, a randomly selected BrP was applied. Data acquisition and statistical analysis Signals were captured simultaneously breath by breath using Quark CPET hard- ware and software (Cosmed, Italy); arterial blood pressure and ECG were recorded by DATAQ system (DATAQ instruments Inc., DI-720 series, Ohio, USA). For analy- sis, three separate intervals were determined: the last three minutes of sitting rest (baseline), the last three minutes of cycling (exercise), and the last three minutes of recovery (recovery). Oxygen consumption per body mass (VO2/kg), CO2 production per kg (VCO2/kg), respiratory exchange ratio (RER), ventilator equivalents (Veq for O2 and CO2), respiratory rate (RR), tidal volume (VT), and heart rate (HR) were determined. The data are presented on graphs as mean values ± standard deviation (SD). Additionally, enhanced post-exercise oxygen consumption (O2 debt) and oxy- gen deficit (O2 deficit) at the onset of exercise were determined using Quark CPET analyzing software (Cosmed, Italy) based on the work of Hughson and Morrissey (Hughson and Morrissey 1983). Statistical analysis was completed using IBM SPSS Statistics, version 27 (IBM, New York, USA). Data were tested for normality and a p<0.05 level of confidence was selected. We compared mean differences in measured parameters over time (before and during exercise + recovery) for all three BrPs with a one-way repeated measures ANOVA (rANOVA). The assumption of sphericity was checked using Mauchly's test; Greenhouse-Geisser or Huynh-Feldt corrections were applied when sphericity assump- tion was violated as published elsewhere (Hopkins, Marshall, Batterham, & Hanin, 2009). When detecting a significant time effect, corresponding contrast tests were used to identify differences between means according to BrP and time interval. For post hoc comparisons a least significant difference test was applied and the Bonferroni correc- tion was used to eliminate type I error in multiple comparisons (Hopkins et al. 2009). In case of significant differences, Cohen’s d was determined to represent the effect size (ES) (Hopkins et al., 2009). 78 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 RESULTS RR increased during exercise in all three BrPs (Figure 1, Table 1), most in BrP1, where the mean value was 22.56 ± 1.1 min-1. RR in BrP1 was significantly higher than in BrP2 (p < 0.001) and BrP3 (p = 0.007). There were no statistical differences between BrP2 and BrP3 (p = 0.103). After exercise, RR dropped as expected, but in the last 3 minutes of recovery it was still higher than the baseline values in all BrPs, but signifi- cantly higher only in BrP1 (p = 0.001) (Table 1). Table 1: Effect sizes presented as Cohen’s d values for all significant differences. RR VT VE RER VO2/kg VCO2/ kg Veq for O2 Veq for CO2 BrP1base/ex 1.59 3.53 6.46 1.34 6.94 6.48 1.50 4.03 BrP1base/rec 0.67 - 1.26 0.80 - - 0.99 0.60 BrP1ex/rec 1.227 3.42 6.27 0.81 6.71 6.58 2,19 3.23 BrP2base/ex 0.41 3.46 4.00 1.18 6.54 6.59 1.81 2.38 BrP2base/rec - - 0.68 - - - 0.82 6.82 BrP2ex/rec 0.22 3.54 5.01 1.43 6.69 6.89 2.44 6.89 BrP3base/ex 0.41 3.24 4.42 1.50 7.49 6.76 1.41 2.40 BrP3base/rec - 0.46 1.10 0.76 - 0.63 1.14 0.63 BrP3ex/rec 0.47 3.23 4.36 0.88 6.55 6.07 1.96 6.37 BrP1ex/BrP2ex 0.72 1.05 - - - - - - BrP1ex/BrP3ex 0.14 0.35 - - - - - - BrP2ex/BrP3ex - 0.72 - - - - - - BrP1 – breathing pattern 1, BrP2 - breathing pattern 2, BrP3 – breathing pattern 3, base – base- line, ex – exercise, rec – recovery, RR – respiratory rate, VT – tidal volume, VE – ventilation, RER – respiratory exchange ratio, VO2 /kg – oxygen consumption per body mass, VCO2 /kg – carbon dioxide production per body mass, Veq for O2 – ventilatory equivalent for oxygen, Veq for CO2 - ventilatory equivalent for carbon dioxide. 79 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 Figure 1: Changes in RR during rest, exercise and recovery in different BrPs. Values are presented as the mean ± SD. * - significant difference between BrP1 and BrP2, # - significant difference between BrP1 and BrP3, § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. Figure 2: Changes in tidal volume during rest, exercise and recovery in different BrPs. Values are presented as the mean ± SD. * - significant difference between BrP1 and BrP2, # - significant difference between BrP1 and BrP3, ‡ significant difference be- tween BrP2 and BrP3, § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. 80 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Figure 2 shows the changes in VT, related effect sizes are presented in Table 1. The value increased the most in the group with BrP2, which had the lowest RR during exer- cise. We found significant differences between all three BrP; the statistical difference between BrP1 and BrP2 was p < 0.001, between BrP1 and BrP3 p = 0.016 and between BrP2 and BrP3 p = 0.002. As can be seen from Figure 2, the values returned to baseline values at recovery; only in BrP3 did we find a significant difference between baseline and recovery (p = 0.008). During exercise ventilation increased (Figure 3, Table 1), but no significant diffe- rences were found between the groups. During the recovery, the values dropped but not to baseline values. Ventilation in recovery was significantly higher compared to baseli- ne (p <0.001 for BrP1 and BrP3, and p = 0.003 for BrP2, respectively). Figure 3: Changes in ventilation during rest, exercise and recovery in different BrPs. Values are presented as the mean ± SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. Figure 4 shows the changes in RER. No significant differences were found betwe- en BrPs; related effect sizes are reported in Table 1. In recovery, the RER remained elevated above the resting value. It was significantly higher in the groups with BrP1 (p < 0.001) and BrP3 (p = 0.001); in the group with BrP2 we did not find a difference (p = 0.333). As expected, VO2/kg increased during exercise and remained increased at the end of the measurement (Fig. 5, Table 1). As can be seen from Figure 5, no significant differen- ces were observed with regard to BrPs, neither at rest nor during exercise or recovery. 81 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 Figure 4: Changes in respiratory exchange ratio during rest, exercise and recovery in different BrPs. Values are presented as the mean ±SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. Figure 5: Changes in oxygen consumption during rest, exercise and recovery in differ- ent BrPs. Values are presented as the mean ±SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery. 82 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Regarding VCO2/kg, there were no significant differences between groups during rest and exercise, we did, however, find a significant difference between baseline and recovery in BrP3 (P < 0.001) (Fig. 6, Table 1). Figure 6: Changes in production of carbon dioxide during rest, exercise and recovery in different BrPs. Values are presented as the mean ± SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in a particular BrP between rest and recovery. Figure 7 presents the change in VEq for O2. No statistical differences were found between the groups in any of the phases, but a higher value was observed in the BrP2 and BrP3 groups at rest and lower during exercise compared to BrP1. We found a sta- tistical difference between baseline and exercise as well as between rest and exercise with respect to recovery, which was p < 0.001 in all BrPs (Table 1). No significant differences between groups were observed during exercise and reco- very in Veq for VCO2 (Figure 8). Statistical differences were observed between baseline and recovery. In the group with BrP1 the difference was p = 0.009; in the group with BrP2 p = 0.007; and in the group with BrP3 p = 0.002. Veq for CO2 was significantly increased during exercise compared to rest or recovery (p < 0.001) (Table 1). 83 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 Figure 7: Changes in ventilatory equivalent of oxygen during rest, exercise and recov- ery in different BrPs. Values are presented as the mean ± SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. Figure 8: Changes in ventilatory equivalent of carbon dioxide during rest, exercise and recovery in different BrPs. Values are presented as the mean ± SD. § - significant difference in all BrPs between rest and exercise, Ω - significant difference in all BrPs between exercise and recovery, ∞ - significant difference in all BrPs between rest and recovery. 84 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Figure 9 shows O2 deficit and O2 debt throughout the three BrPs. O2 deficit (but not O2 debt) in spontaneous breathing was significantly higher compared to other BrPs (ES = 0.42 for BrP1 compared to BrP2 and 0.36 for BrP1 compared to BrP3, respecti- vely). O2 debt was significantly lower compared to O2 deficit in all BrPs (ES = 0.87 for BrP1, 0.20 for BrP2 and 0.15 for BrP3, respectively). Figure 9: Changes in oxygen deficit (O2 deficit) and oxygen debt (O2 debt) throughout all breathing patterns: spontaneous breathing (BrP1), pronouncing “h” (BrP2) and pronouncing “sh” (BrP3), respectively. * - significant with respect to BrPs. # - deficit versus debt. DISCUSSION Our first main finding was that phonation during moderate exercise has a minimal effect on the respiratory response to exercise and recovery in young, healthy partici- pants. Our second main finding was that phonated breathing during moderate exerci- se provoked an increased rate of perceived exertion compared to spontaneous bre- athing. And our third main finding was that oxygen deficit at the onset of moderate exercise is significantly higher in spontaneous compared to phonated breathing. On the other hand, EPOC was not affected by BrP, indicating that in a steady state during moderate exercise excessive oxygen deficit was successfully eliminated by aerobic metabolism. 85 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 Although not significantly different, evidently lower RER during steady state exer- cise in BrP3 compared to other BrPs suggested that restricted air flow during expira- tion may cause CO2 retention. This assumption was supported by the increased CO2 exhalation in the recovery phase after exercise (Fig.6) in BrP3. Additionally, during steady state exercise, RR in BrP3 was higher compared to that in BrP2, presumably because of the stimulation of the inspiratory center by increased arterial CO2 partial pressure. RR during spontaneous breathing was significantly increased compared to those in both BrP2 and BrP3 because of phonation excluding prolonged exhalation. Breathing against increased airway expiratory resistance (pronunciation of “sh”) versus open airway expiration (pronunciation of “h”) does not appear to alter airway diameter sufficiently to augment the minute ventilation response during moderate exercise. Even upon spontaneous breathing, minute ventilation was not changed compared to phonated breathing patterns. The similar minute ventilation across all BrPs at steady state moderate exercise corresponding to an oxygen uptake of 23.5 mL/kg/min suggests that all BrPs applied can accommodate a moderate level of exercise intensity in young healthy participants (Plowman and Smith n.d.). In our study, VO2 did not differ during moderate physical activity at different BrPs. This finding is not in compliance with our previous study, where the reduced VO2 in the low-intensity trunk stabilization exercise with hand-oscillation was confirmed upon phonated exhalation while pronouncing “sh” (Klanjšček, 2018). One possible explanation for this could be that the participants breathed in respiratory coupling with locomotion in the previous study. The entrainment could be responsible for better bre- athing economy (Sporer, Foster, Sheel, & McKenzie, 2007). Further, VO2 was measu- red at the onset of trunk stabilization exercise in our previous study and not during the steady state, and thus was accompanied by anaerobic metabolism. When substituting anaerobic metabolism with aerobic in the continuation of trunk stabilization exercise, the differences in VO2 between different BrPs decreased. This could imply that as the exercise is aerobic, the beneficial effects of PEP exhalation are decreased. The association between anaerobic metabolism and breathing economy in connec- tion to the use of a mouthguard was established (Schulze, Kwast, & Busse, 2019). The results of the studies examining the effect of different mouthguards on athletes’ performance concluded that the economy of breathing is improved by wearing mouth- guards at high but not moderate exercise intensities (Lässing et al., 2021; Schulze et al., 2019). The mechanism proposed is altered exhalation, potentially against higher resistance produced by mouthguards (Schulze et al., 2019). The impact of breathing using mouthguards is being researched in connection with sports that due to their nature need this type of protection (such as rugby and hockey) (Phimphasak et al., 2018; Schulze et al., 2019). Studies including young healthy athletes have found that altered exhalation due to wearing this equipment reduces the proportion of anaerobic metabolism at high-intensity exertion, compared to unmodified exhalation when not wearing it (Lässing et al., 2021). Francis and colleagues (Francis & Brasher, 1991) de- scribed reduced VO2 and VEq for O2 upon mouthguard usage at high-intensity exercise 86 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 but not at low-intensity exercise. Since we did not confirm the beneficial effect of BrP3 in our study, we may speculate again that the beneficial effect of phonated expiration is limited to predominantly anaerobic or high-intensity load. Additional investigations should be conducted to test this assumption. Phonated exhalation can be compared to breathing with pursed lips. There are some articles about the effects of pursed lip breathing on the breathing load, but only resear- ched in patients with impaired pulmonary function (Sakhaei, Sadagheyani, Zinalpoor, Markani, & Motaarefi, 2018). Sakhaei and colleagues (Sakhaei et al., 2018) found that in patients with COPD, oxygenation and CO2 excretion improve – as respiratory work is reduced - upon PEP provoked by pursed lips, while De Araujo (Pereira De Araujo, Karloh, Martins Dos Reis, Palú, & Fleig Mayer, 2015) and colleagues found that this type of breathing reduces dynamic hyperinflation, improving tolerance for exercise and O2 saturation in the blood during exercise in COPB. Breslin (Breslin, 1992) found that spontaneous rhythmic breathing through pursed lips can affect the coordination of respiratory muscle recruitment and provides patients with a sense of control over venti- lation, which results in less anxiety, panic, and consequently reduces dyspnea. Exercise in healthy participants can be seen as a model of impaired pulmonary function, as it increases the load on the respiratory system due to increased need for O2 and produces more CO2. Based on our results we can conclude that the intensity of moderate exercise applied in our study was not high enough to reveal the advantages of PEP breathing du- ring exercise in young healthy adults. The physiological effects of phonated breathing in COPB patients should be examined to determine the potential benefits of phonated exhalation (decrease exercise respiratory load and perceived exertion) during exercise in such patients. We found a significantly increased O2 deficiency at the onset of moderate exercise upon spontaneous breathing compared to both phonated breathing patterns, indicating that spontaneous respiration was the least economical at the onset of exertion. On the contrary, the EPOC did not differ with regard to BrP. This finding supports our specula- tion that beneficial effects of breathing against increased airway expiratory resistance, as in the pronunciation of “sh”, are manifested only when exercise metabolism is pre- ferentially anaerobic. EPOC is decreased compared to O2 deficit at spontaneous bre- athing, presumably because the products of anaerobic metabolism were removed and aerobically metabolized during steady state exercise due to its low intensity. O2 deficit and EPOC did not differ with respect to the sound pronounced. Further studies should be directed to explain this finding. Bonsignore and colleagues (Bonsignore, Morici, Abate, Romano, & Bonsignore, 1998) chose the VEq for O2 and CO2 as the main measure of respiratory efficiency. In our study, we found that both VEq for O2 and CO2 decreased during physical exertion compared to baseline, indicating that moderate exercise made the respiration more effi- cient (Plowman & Smith, n.d., 2013); and there were no significant differences between individual BrPs. Differences were indicated, yet not significant: both VEq upon BrP2 and BrP3 during exercise were lower than during spontaneous respiration. These ob- servations can be linked to a study by Francis and Brasher (Francis & Brasher, 1991) 87 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Kaja STANKOVIĆ, Nejka POTOČNIK: THE EFFECT OF PHONATED BREATHING ON OXYGEN UPTAKE ..., 73–89 who found a lower Veq for O2 in subjects wearing mouthguards, indicating improved alveolar ventilation and oxygenation that allows an individual to maintain a certain level of exercise with less loss to the metabolic system; and to a study by Delaney and Montgomery (Delaney & Montgomery, 2005), who found that mouthguards obstruct airflow and thus affect VO2 and ventilation during strenuous exercise. Again, both stu- dies have demonstrated greater breathing efficiency in subjects using mouth protective devices only at maximum load. There are some limitations to this research: in all participants the same load (140 W for males and 100 W for females) was applied as moderate exercise, neglecting indi- vidual differences, and the correctness of breathing pattern implementation was not controlled as the participant’s mouth was covered by a breathing mask. In conclusion, we found no physiological benefits of phonation applied upon mode- rate exercise that could advocate its use for economizing breathing at higher metabolic demand. However, decreased oxygen deficit at the onset of moderate exercise upon phonated compared to spontaneous breathing confirmed its positive effects on the ana- erobic phase at the onset of exercise. This finding may potentially provide benefits for patients with compromised respiratory function owing to an enhanced proportion of anaerobic metabolism even at moderate exercise loads, however, further studies need to be conducted to test this assumption. 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ANNALES KINESIOLOGIAE • 12 • 2021 • 2 91 Original scientific article DOI: https://doi.org/10.35469/ak.2021.324 received: 2022-04-01 UDC: 796.82:613.24 THE EFFECT OF RAPID WEIGHT LOSS ON THE HANDGRIP STRENGTH OF NATIONAL-LEVEL WRESTLERS Carlo ROSSI1, Roberto ROKLICER2, Antonino BIANCO1, Marko MANOJLOVIC2, Barbara GILIC3,4, Tatjana TRIVIC2 and Patrik DRID2 1 Sport and Exercise Sciences Research Unit, University of Palermo, Palermo, Italy 2 Faculty of Sport and Physical Education, University of Novi Sad, Serbia 3 University of Split, Faculty of Kinesiology, Split, Croatia 4 University of Zagreb, Faculty of Kinesiology, Zagreb, Croatia Corresponding author: Patrik DRID University of Novi Sad, Faculty of Sport and Physical Education, Lovćenska 16, 21000 Novi Sad, Serbia Phone: +381641118884 E-mail: patrikdrid@gmail.com ABSTRACT The effects of rapid weight loss (RWL) in combat sports athletes is an area that is not yet fully discovered. Therefore, the goal of this study was to determine the impact of weight loss on HGS (handgrip strength) in Greco-Roman wrestlers. This cross-over study included ten athletes examined for HGS during three time points for each hand. The first measurement – baseline (BL), was performed before we- ight reduction. The second measurement ‒ phase 1 (P1), was taken after high-intensity sports specific training (HISST) combined with RWL. In this phase, participants had to lose 5% of their body mass within three days, after which HISST was carried out (on day 3). The third measurement ‒ phase 2 (P2), was performed seven days after P1, which included HISST with no RWL. When comparing the HGS values, significantly higher values were observed only when P1 was compared with P2 for the left hand (p=0.039). This means that the grip was significantly stronger after RWL was conducted together with HISST. This research could be of great importance to combat sports coaches and athletes as it evaluates the effect of RWL on performance parameters. Therefore, the results of our study could serve to improve the wrestlers’ weight-reduction plan. Keywords: Greco-Roman, performance, weight reduction, wrestling 92 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 UČINKI NAGLEGA ZMANJŠEVANJA TELESNE MASE NA MOČ OPRIJEMA PRI REPREZENTANČNIH ROKOBORCIH IZVLEČEK Učinki naglega zmanjševanja telesne mase pri športnikih v borilnih disciplinah so področje, ki še ni povsem raziskano. Zato je bil cilj te študije ugotoviti, kako nagla izguba telesne mase vpliva na moč oprijema pri rokoborcih v grško-rimskem slogu. V pričujočo navzkrižno študijo smo vključili deset športnikov, pri katerih smo pre- verjali moč oprijema za vsako roko v treh različnih časovnih obdobjih. Prvo meritev ‒ ki je predstavljala izhodišče ‒ smo opravili pred začetkom zmanjševanja telesne mase. Drugo meritev ‒ 1. faza ‒ smo opravili po visokointenzivni športnospecifični vadbi v kombinaciji z naglo izgubo telesne mase. V tej fazi so sodelujoči morali v treh dneh za 5 odstotkov zmanjšati svojo telesno maso, nato pa opraviti visokointenzivno športnospecifično vadbo (tretji dan). Tretja meritev ‒ 2. faza ‒ je bila izvedena se- dem dni po 1. fazi in je vključevala visokointenzivno športnospecifično vadbo brez zmanjševanja telesne mase. Pri primerjavi podatkov o moči oprijema smo občutno višje vrednosti zaznali med rezultati meritev v 1. in 2. fazi za levo roko, saj so slednji pokazali, da se je moč opri- jema občutno povečala po zmanjšanju telesne mase v kombinaciji z visokointenzivno športnospecifično vadbo. Študija, ki meri učinke naglega zmanjšanja telesne mase na parametre zmogljivosti, prinaša pomembne uvide za trenerje in športnike v borilnih disciplinah in bi lahko pripomogla k izboljšanju programov za zmanjševanje telesne mase pri rokoborcih. Ključne besede: grško-rimski slog, zmogljivost, zmanjševanje telesne mase, rokoborba ANNALES KINESIOLOGIAE • 12 • 2021 • 2 93 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 INTRODUCTION To be successful in wrestling, an athlete must possess high levels of physical and psychological readiness. Indeed, wrestling is a very demanding and vigorous sport that consists of two 3-minute rounds, with a break of 30 seconds in between (Yoon, 2002). Thus, both aerobic and anaerobic energy systems are taxed during a wrestling match (Nikooie, Cheraghi, & Mohamadipour, 2017). Specifically, the anaerobic system pro- vides explosive and short bursts of maximal power and strength, while the aerobic sy- stem is responsible for sustained effort during the match (Demirkan, Koz, Kutlu, & Fa- vre, 2015). Furthermore, wrestling requires highly developed upper-body strength and power, particularly handgrip strength (Gerodimos et al., 2013; Demirkan et al., 2015). Handgrip strength (HGS) in hand-to-hand combat sports, including wrestling, is es- sential for movements such as pulling, pushing, throwing and controlling the opponent, which are important determinants of the match outcome (Cronin, Lawton, Harris, Kild- ing, & McMaster, 2017). Moreover, possessing high HGS and endurance is very im- portant in the later rounds of the match and can influence the continuation or end of the dominance of the opponent (Franchini, Schwartz, & Takito, 2018). Also, HGS is essen- tial in several wrestling holds because various take-down and defensive maneuvers are based on a strong grip (Gerodimos et al., 2013). Indeed, a very strong relationship was recorded between HGS and success in wrestling (i.e., competition ranking) (García- Pallarés, López-Gullón, Muriel, Díaz, & Izquierdo, 2011; Nikooie et al., 2017). Also, elite male wrestlers had stronger handgrip compared to sub-elite wrestlers (Nikooie et al., 2017). It is important to note that both absolute and relative strength was higher in elite than in sub-elite wrestlers, which supports the hypothesis that handgrip can be observed as a determinant of overall strength in athletes (García-Pallarés et al., 2011). In combat sports, athletes are categorized into weight classes according to their body mass in order to reduce the difference in strength and size of the competitors. The aim of dividing athletes into weight classes is to create equal competition conditions for each athlete (Castor-Praga, Lopez-Walle, & Sanchez-Lopez, 2021). However, in order to drop the weight into a class where an athlete would have an advantage over the lighter and weaker opponent, rapid weight loss is commonly practiced among combat sports athletes (Khodaee, Olewinski, Shadgan, & Kiningham, 2015; Ranisavljev et al., 2022; Todorović et al., 2021). Rapid weight loss (RWL) stands for a method characteri- zed by losing at least 5% of body weight in fewer than seven days prior to competition (Khodaee et al., 2015). However, such large alterations in body weight, although wi- thout conclusive scientific evidence, most likely impact athletes’ performance. Namely, RWL leads to detriments on anaerobic performance, which is related to reduced glyco- gen depletion and buffering capacity (Lakicevic et al., 2020). Reduced muscle glyco- gen can impair excitation-contraction coupling in the muscle and accelerate the onset of muscle fatigue, which can reduce exercise performance (Ørtenblad, Westerblad, & Nielsen, 2013). Recent studies revealed that RWL leads to significant muscle damage in combat sports athletes and impairs heart rate recovery in national-level wrestlers (Roklicer et al., 2020; Roklicer et al., 2022). 94 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 To the best of the authors’ knowledge, no study has examined the influence of RWL combined with HISST on HGS in wrestlers. Thus, the aim of this study was to determi- ne the impact of RWL on HGS in wrestlers. METHODS Participants This cross-over study was carried out on a total of 10 male national level Greco- Roman wrestlers (22.44 ± 4.53 years; mean body weight: 73.36 ± 4.42 kg; mean body height: 174.43 ± 3.78 cm). To be included in the experiment, wrestlers had to have at least five years of competitive experience. Additionally, participants were eligible only if they had used RWL methods within the previous two years. Participants were free of injury at the time of the testing. The procedures were fully explained to the participants before conducting the study. Each respondent participated voluntarily by signing the informed consent. Body composition parameters were measured using a body compo- sition analyzer (Omron BF511, Omron Healthcare Ltd., Matsusaka, Japan). All procedures were carried out in accordance with the Declaration of Helsinki. The study was approved by the ethical board of the University of Novi Sad, Serbia (Ref. No. 46-06-02/2020-1). Experimental Approach to the Problem Handgrip strength was measured at three time points. The first measurement – (BL) was conducted before the weight reduction. The second measurement – Phase 1 (P1), was done after the high-intensity sport-specific training (HISST) combined with RWL. For this phase, participants had to lose 5% of their body mass within three days, after which the HISST was carried out (on day 3). The third measurement – Phase 2 (P2), was carried out seven days following P1 and included HISST (after which the measu- rements were done) with no RWL. Isometric Handgrip Strength The maximum grip strength was measured for both hands with a Takei portable dynamometer (Takei Scientific Instruments Co., Tokyo, Japan). Participants stood with the abducted shoulder. The dynamometer was previously adapted to the size of the participant’s hands and held with the arms parallel to the body without squeezing/at- taching the arm against the body. The position of the hand remained constantly down- wards, and the palm did not bend at the wrist joint. Subjects were asked to do a maxi- ANNALES KINESIOLOGIAE • 12 • 2021 • 2 95 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 mum voluntary contraction on the dynamometer for 5 seconds. All subjects performed three trials for each hand, and the best performance was used for further analysis. Statistical Analysis The results are presented as mean and standard deviation. The normality of the dis- tribution was determined by the Shapiro-Wilks test. To compare the means between the handgrip strength measurements, One Way ANOVA for repeated measures with LSD post hoc analysis was conducted. All statistical procedures were done using IBM SPSS Statistics for Windows, 20.0 (IBM Corp 20, Armonk, NY, USA). The significance level was set at p≤0.05. RESULTS The wrestlers’ characteristics are presented in Table 1. According to the results obta- ined, statistically significant differences were observed across the three time points. The values obtained in P1 were significantly lower for body weight, BMI, FM, and VBF, while muscle mass increased significantly compared to the baseline measurement. The results in P2 were significantly higher for body weight, BMI, FM, and VBF, while mu- scle mass was significantly lower in this phase compared to P1. Basal metabolic rate was not significantly different across the three time points. Table 1. Descriptive characteristics of body composition of wrestlers (n=10) BL P1 P2 Body weight (kg) 73.36±4.42 69.27±4.12* 72.38±4.17# BMI (kg/m2) 24.11±0.96 22.62±0.98* 23.64±1.07# FM (%) 16.37±2.22 12.74±3.15* 14.98±2.47# MM (%) 42.51±1.41 44.64±2.14* 43.36±1.71# VBF (%) 6.11±1.05 4.88±1.16* 5.66±1.32# Basal metabolic rate (kcal) 1717.33±64.98 1677.11±61.49 1704.11±56.43 Values are presented as mean and standard deviation (M±SD); BL – baseline values; P1 – phase one: HISST combined with RWL; P2 – phase two: HISST with no RWL procedures included; BMI – Body mass index (kg/m2); FM – Fat mass (%); MM –muscle mass (%); VBF – Visceral body fat (%);* statistically significant difference compared to baseline values, p≤0.001; # statistically significant difference compared to P1, p≤0.01. 96 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 The handgrip strength values for both hands are presented in Table 2. Although the higher values for the right hand are visible in P1 and P2 in comparison to the baseline, the difference remained statistically insignificant. As for the left hand, similar values were obtained during BL and P2. However, according to LSD pairwise comparisons, significantly higher handgrip strength was observed in P1 only when compared to P2, p=0.039 (Figure 1). Figure 1. Handgrip strength differences in Greco-Roman wrestlers. Legend: * - significantly different compared to P2 (left handgrip) p<0.05; BL – baseline meas- urement; P1 – phase one: HISST combined with RWL; P2 – phase two: HISST with no RWL procedures included; HG – right and left handgrip strength; kg – kilograms. ANNALES KINESIOLOGIAE • 12 • 2021 • 2 97 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 Table 2. Handgrip strength of wrestlers. BL P1 P2 F p Partial Eta squared HG right (kg) 55.55 ±5.81 56.66 ±7.28 56.44 ±8.35 0.104 0.857 0.013 HG left (kg) 54.55 ±6.06 57.55 ±4.44* 54 ±4 1.845 0.199 0.187 Values are presented as mean and standard deviation (M±SD); BL – baseline values; P1 – phase one: HISST combined with RWL; P2 – phase two: HISST with no RWL procedures included; F – F ratio; HG right – right-hand handgrip strength; HG left – left-hand handgrip strength; *statistically significantly different compared to P2 according to post hoc pairwise comparisons, p≤0.05. DISCUSSION To the author‘s knowledge, this is the first cross-over design study that analyzes the impact of combining RWL with HISST and HISST alone on HGS performance in nati- onal-level Greco-Roman wrestlers. The obtained results demonstrated changes in HGS values in the phase when body weight reduction was implemented. Maximum grip strength production significantly increased only for the left hand of the athletes. There are not many previous studies examining the influence of RWL on HGS in wrestlers. Research conducted on elite wrestlers showed a decrease in HGS performance after applying RWL (Jlid, Maffulli, Elloumi, Moalla, & Paillard, 2013). On the other hand, weight loss failed to alter the HGS values in college wrestlers (Serfass, Stull, Alexan- der, & Ewing Jr., 1984; Marttinen, Judelson, Wiersma, & Coburn, 2011). In contrast to the results of these studies, this research reported a positive effect of RWL on HGS values. Isometric strength production was higher for the left hand during the combi- ned phase of RWL with HISST compared to values observed in P2. The average HGS performance of the right hand was also increased, albeit without statistical significan- ce. Several possible mechanisms may explain these findings. Athletes have probably experienced psychological arousal due to reaching the target weight for the category in which they intend to compete, which potentially leads to improved strength performan- ce. Additionally, changes in body composition may be related to the results shown. The increase in muscle mass, as well as the decrease in FM and VBF during the application of RWL, are probably responsible for the positive alterations in HGS values. Due to the already mentioned importance of HGS in separating more successful wrestlers from less successful ones, coaches and athletes could probably implement RWL before the competition. Of course, the weight loss process must be conducted with some caution due to the negative impact on other health aspects of athletes. Future studies on larger 98 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 samples are needed to clearly understand the results obtained in this study. In combat sports, the link between weight loss and HGS has been most investigated in judo. As in wrestling, the previous findings are inconsistent. Some studies have reported that RWL reduces HGS values in judo athletes (Degoutte et al., 2006; Clarys, Ramon, Hagman, Deriemaeker, & Zinzen, 2010; Isacco et al., 2020). However, the weight loss did not change the HGS performance of the left hand in national level judokas (Filaire et al., 2001). Additionally, weight reduction did not affect the maximal isometric strength in Czech judokas, although marginally higher average HGS values were observed for both the left and right hand after the RWL period (Coufalová, Cochrane, Maly, & Hel- ler, 2014). The results are also in conflict in Mixed Martial Arts (MMA). Camarço et al. (2016) failed to find alterations in HGS values after RWL was applied. Contrary, RWL significantly decreased HGS performance in amateur MMA fighters (Alves et al., 2018). All studies demonstrated a negative or no effect of RWL on HGS values in combat athletes. Only the results of our research showed a positive impact of RWL on HGS performance. The cross-over design of the presented study may be a factor that contributed to the final outcome. Some of the future research could focus on the influ- ence of RWL on HGS in combat sports like sambo, taekwondo, or boxing. Finally, this study has several relevant limitations that should be mentioned. First, the study was conducted on a relatively small sample . Second, the respondents were national-level wrestlers. Participants’ hand dominance was not reported prior to testing. Future studies should monitor glycogen and various inflammation and muscle damage levels along with subjective levels of physical and/or mental arousal. Additionally, future studies should investigate the impact of RWL on HGS values in elite wrestlers. Finally, athletes were free to choose weight loss methods. Hence, wrestlers most likely used different techniques of RWL. CONCLUSION The aim of this study was to determine HGS in national-level wrestlers. Particular- ly, the impact of RWL on the handgrip strength was measured during baseline and two different phases ‒ P1 and P2. Comparing the HGS values, a significant difference was observed only when P1 was compared to P2 for the left hand. Specifically, the handgrip was stronger after RWL was included along with HISST. This phenomenon may be interpreted as psychological arousal of athletes who have attained the target weight for a certain category they tend to compete in. This research could be of great importance for combat sports coaches and athletes as it evaluates the effect of RWL on performance parameters. Although further studies on this matter would be of great importance, the findings of our study might serve to improve the wrestlers’ weight reduction plan. ANNALES KINESIOLOGIAE • 12 • 2021 • 2 99 Carlo ROSSI, Roberto ROKLICER, Antonino BIANCO, Marko MANOJLOVIC, Barbara GILIC, Tatjana TRIVIC and Patrik DRID: THE EFFECT ..., 91–101 Conflict of Interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. REFERENCES Alves, R. C., Alves Bueno, J. C., Borges, T. O., Zourdos, M. C., de Souza Junior, T. P., & Aoki, M. S. (2018). Physiological function is not fully regained within 24 hours of rapid weight loss in mixed martial artists. Journal of exercise physiology online, 21(5). Retrieved from https://www.asep.org/asep/asep/JEPonlineOCTOBER2018_Alves.pdf. Camarço, N. 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ANNALES KINESIOLOGIAE • 12 • 2021 • 2 103 CORRELATIONS BETWEEN MOTOR AND ANTHROPOMETRIC VARIABLES AND THE PERFORMANCE OF YOUNG COMPETITORS IN ALPINE SKIING Stojan PUHALJ1, Blaž LEŠNIK2, Alexander POVHE2, Robi KELC3, Črtomir MATEJEK1 1 University of Maribor, Faculty of Education, Maribor, Slovenia 2 University of Ljubljana, Faculty of Sport, Ljubljana, Slovenia 3 University of Maribor, Faculty of Medicine, Maribor, Slovenia Corresponding author: Stojan PUHALJ University of Maribor, Faculty of Education, Koroška cesta 160, 2000 Maribor, Slovenia Tel.: +386 2 229 37 41 e-mail: stojan.puhalj@um.si ABSTRACT In alpine skiing we encounter many factors that affect the competitor to a greater or lesser extent and must be overcome or exploited in various ways. Broadly speaking, the nature of the activity plays its role just like the equipment, the spectators, the coach, etc., but the most important role is played by the competitor himself. Optimal synthesis is required for successful participation of top competitors with regard to physical, psycho- logical and social skills and characteristics. During the transformation process (training) we help the competitor with different methods and means to transform from the initial to the final state, which is basically conscious transformation of numerous skills and characteristics of the competitor with impact on their personality as well. In this study we wanted to establish the extent to which certain anthropometric and motor skill parameters are related to competitive performance of younger boys aged 12 to 13 years in the Rauch Cup in the season 2014/15. Based on the measurements of se- ven tests of motor skills (MSKOK10 – Ten jumps with both feet, TESJCAS – Squat jump, MS20NVZP – 20m sprint, TREAOPTO – Optojump – Squat jump, MT400 – 400m run, MROS - Equilibrium stability index, and SKI9 – Figures-of-eight around 9 pins) and one measurement of anthropometric dimension (ABMI - Body Mass Index), we used the Pear- son correlation coefficient to determine the correlation between individual variables and the performance of a sample of 34 young competitors in alpine skiing. The correlation of the whole set of variables regarding performance was determined using regression analysis. We have established a statistically significant correlation between the number of Original scientific article DOI: https://doi.org/10.35469/ak.2021.338 received: 2022-08-22 UDC: 796.926:796.012.1 104 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 achieved points and variables MSKOK10, MS20NVZP, MT400 and SKI9 at the risk level of 1%. In the cases of TREAOPTO, MROSI and TESJCAS the correlation coefficients did not show statistically significant correlation. For the set of motor and anthropometric variables we have established a high and statistically significant linear correlation to the criteria (R=0.76, p=0.003). We have also established that the linear correlation between all motor skill variables and performance is high (R=0.72, p=0.006). The findings of this study show the suitability of the chosen variables in determining the potential success of young alpine skiers. Keywords: alpine skiing, young competitors’ performance, motor abilities, anthro- pometry POVEZANOST ANTROPOMETRIČNIH IN MOTORIČNIH SPREMENLJIVK Z USPEŠNOSTJO MLAJŠIH DEČKOV V ALPSKEM SMUČANJU IZVLEČEK V raziskavi smo ugotavljali, v kolikšni meri so določeni antropometrični in moto- rični parametri povezani s tekmovalno uspešnostjo mlajših dečkov na tekmovanjih za pokal Rauch v sezoni 2014/15. Na podlagi meritev sedmih testov motoričnega prostora (MSKOK10, TESJCAS, MS20NVZP, TREAOPTO, MT400, MROSI, SKI9) in ene meritve antropometričnega prostora (ABMI), smo s pomočjo Pearsonovega korelacijskega koefi- cienta ugotavljali povezanost posameznih spremenljivk z uspešnostjo za vzorec 34 mlaj- ših dečkov, ki so bili v smučarski sezoni 2014/15 stari 12 oz. 13 let. Povezanost celotnega sklopa spremenljivk motoričnih in antropometričnih prostorov s tekmovalno uspešnostjo smo ugotavljali s pomočjo regresijske analize. Kriterijsko spremenljivko Tekmovalna uspešnost je predstavljalo skupno število doseženih točk šestih pokalnih tekmovanj za pokal Rauch v sezoni 2014/15. Ugotovili smo, da statistično značilna povezanost med šte- vilom doseženih točk in spremenljivko ABMI ne obstaja. Stopnja povezanosti je neznatna in negativna (r = -0,023). Ugotovili smo, da obstaja statistično značilna povezanost med številom doseženih točk in spremenljivkami MSKOK10, MS20NVZP, MT400 in SKI9 pri stopnji tveganja 1 %. V primeru TREAOPTO, MROSI in TESJCAS izračun korelacijskih koeficientov ni pokazal statistično značilne povezanosti. Za sklop vseh motoričnih in an- tropometričnih spremenljivk smo ugotovili, da je linearna povezanost s kriterijem visoka (R=0,76, p=0,003). Ugotovili smo tudi, da je linearna povezanost med vsemi motorični- mi spremenljivkami hkrati in kriterijem visoka (R=0,72, p=0,006). Ugotovitve raziskave kažejo na ustreznost izbire spremenljivk pri ugotavljanju potencialne uspešnosti mladih alpskih smučarjev. Ključne besede: alpsko smučanje, uspešnost mladih tekmovalcev, gibalne sposobno- sti, morfologija ANNALES KINESIOLOGIAE • 12 • 2021 • 2 105 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 INTRODUCTION Modern skiing (alpine skiing) is a complex, high-speed winter sport. Dynamic changes and operational structures impose increasing requirements on athletes - a solid base of technical skills, physical, tactical, and psychological training. An alpine skier is first and foremost an athlete whose body should function synchronously, like a perfect mechanism, in the specific conditions of the different disciplines of alpine skiing and depending on a wide variety of environmental variables, to be able to achieve their athletic potential (Kostadinov & Yordanov, 2021). Alpine skiing is a winter sport that involves individual descents on snow slopes with pre-determined ski routes using skis and attached bindings. The competitions are organized according to a certain order, in which all competitors see the results at the end of the competition (Toma et al., 2019). There are many factors that affect the competitor to a greater or lesser extent and must be overcome or utilized in various ways. The skier’s successful performance depends on many variables. Alpine skiing is one of the most complex disciplines to analyze as the skier trajectory is curved and the athlete is moving within a broad open space, down the slope according to the directions and finish, the snow/snow base (moving the body upwards and downwards) and gates (left and right movement) (Erdmann et al., 2017). Generally, the natural environment with various weather conditions plays just as im- portant a role in competitive alpine skiing as the equipment, the spectators, the coach, etc. However, the most important are the competitors themselves. Optimal synthesis is required for successful participation of top competitors with regard to physical, psycho- logical and social skills and characteristics. During the transformation process (train- ing) we help the competitor with different methods and means to transform from the initial to the final state, which is basically conscious transformation of numerous skills and characteristics of the competitor with impact on their personality as well (Petrović, Šmitek & Žvan, 1983). According to Petrović et al. (1983), the psychosomatic status is defined as multidimensional and suprasummative in terms of its effects, indicating that a change in a certain factor conditions a change of other factors. Human movement depends on human motor functions/mobility, characteristics, and skills according to Pi- stotnik (2011). Skills are natural human features, representing the level of utilization of different body management systems for achieving the movement objectives set. It can be said that success in alpine skiing largely depends on the degree of accepted and built specific motor skills (Kuna, Franjko, & Males, 2008). The characteristics are dimensi- ons representing the human appearance and their reaction to the environment, whereas skills or knowledge are defined by learning the acquired movement patterns, which are realized on the basis of abilities and characteristics. Motor skills are indispensable components of human physical activity, enabling the potential for specific efforts and utilization of the body’s functional potential. They develop naturally up to a certain le- vel, depending on many factors, and can be perfected through practice (Plastoi, 2018). The anthropometric methods, defined as measurement of the dimensions of the human body, also have a significant impact on successful competitive alpine skiing (Cramer & Rayan, 2012). Hadzic, Bjelica, Georgiev, Vujovic, and Popovic (2014) analyzed the 106 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 differences in the basic turn technique as one of the ski school elements with regard to anthropometric characteristics. It has been demonstrated that there is a statistically si- gnificant difference in the technique of the basic turn with regard to the anthropometric characteristics of the subjects. Petrović et al. (1983) stated that the ability to kinetically solve spatial problems and timing ability are especially important for alpine skiing, because skiing involves, among other things, different speed combinations of gates and, above all, uneven terrain formation. It could be argued that success, even among young athletes, is mainly the result of properly planned training, talent and hard work. There are only a few who tolerate the psychophysical efforts well and maintain long-term motivation, and even fewer who respond positively to challenges by adapting and ma- king the changes necessary for later top achievements (Bačanac & Škof, 2007). Even in alpine skiing, performance reflects the entire personality of the competitor and must be addressed in a sufficiently complex manner. It consists of several individual skills used under given performance conditions (Ehlenz, Grosser & Zimmermann, 1985). In this study we aimed to establish the extent to which certain anthropometric and motor skill parameters are related to competitive performance of younger male skiers. METHODS The measurements were performed on September 20, 2014 at the Faculty of Sports, University of Ljubljana (Slovenia), in the morning. Students and alpine skiing instruc- tors of the Faculty of Sports, University of Ljubljana assisted in measuring, setting up and organizing. As part of the regular measurements, carried out twice a year, several anthropometric, motor, psychological dimensions and other parameters were measu- red, among which we focused on seven motor and one anthropometric dimension. The measurement was performed in the lobby of the faculty before the subjects headed for warmup to perform motor skill test at the faculty hall, and later for a sprint and 400-me- ter run at the athletic stadium. Participants and recruitment The study included a sample of 34 younger boys who competed in the Rauch Cup in slalom, giant slalom and super giant slalom during the season 2014/15. The overall number of competitors was larger, but only 34 were anthropometrically measured and had their motor skills measured at the Faculty of Sports in October 2014, on account of having achieved a ranking and consequently points at the Rauch Cup. Certain individu- als did not take part in the measurements for subjective reasons. Therefore, we exclu- ded from the sample all those who were not the subject of measurements and those who did not score points during the 2014/15 season. 21 subjects were born in 2001, the other 13 in 2002, belonging to the age categories of 12 and 13 years. ANNALES KINESIOLOGIAE • 12 • 2021 • 2 107 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 Measurement procedures The measurements performed at the Faculty of Sports covered several different anthropometric and motor skills, of which we focused on the following eight: – Anthropometric Body Mass Index (ABMI) – Ten jumps (MSKOK10) – Squat Jump – Tensiometer (TESJCAS) – 20-meter sprint – start with legs parallel (MS20NVZP) – Squat Jump – Optojump (TREAOPTO) – 400-meter run (MT400) – Stability Index – Biodex (MROSI) – Figures-of-eight around 9 pins (SKI9) The criterion variable is the actual performance of all measured competitors at the Rauch Cup during the 2014/2015 season. It is expressed as a total of points in the Rauch Cup competitions. During this season, 2 slalom, 3 giant slalom and 1 super giant slalom races were successfully held at the Rauch Cup, the results of which were considered in the scoring for the final ranking. In these competitions, the ranked competitors achieved a certain number of points for a certain ranking determined by the Skiing Association of Slovenia. Statistical analysis We used the SPSS program - Statistical Package for Social Sciences (IBM Corpo- ration, Armonk, New York, USA) for the statistical data processing. The normality of data was confirmed using the Shapiro-Wilk test. When processing basic statistics of in- dependent variables, we determined the minimum value, the maximum value, the range between the minimum and maximum values, arithmetic mean, and standard deviation. To determine whether we could set the selected variables as comparative performance units of the Rauch Cup, we calculated the Pearson correlation coefficient for each of the eight selected variables in relation to the subjects’ performance. RESULTS The first part of data presentation displays the calculation of basic statistics for anthropometric and motor variables. In the second part of data analysis, we demonstra- ted the calculation of the Pearson correlation coefficients between individual anthro- pometric variables and motor skills in relation to the criterion variable (points at the Rauch Cup competition). The third part represents the calculation of the correlation of all variables with the criterion, for which we performed the regression analysis and 108 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 calculated the multiple correlation coefficient. The same principle of data presentation was applied for the set of motor variables. Table 1. The results of basic statistics of anthropometric and motor variables for young- er boys. N RANGE MIN MAX AM SD ABMI 36 10.3 15.3 25.6 19.88 2.65 MSKOK10 36 9.64 16.04 25.68 19.54 2.23 TESJCAS 36 346 238 584 365.35 75.61 MS20NVZP 36 1.99 5.59 7.58 6.64 .45 MT400 36 34.58 65.56 100.14 79.08 7.94 MROSI 36 3.2 .6 3.8 1.50 .73 SKI9 36 8.1 28.2 36.3 3182 2.16 TREAOPTO 36 .220 .374 .594 .467 .05 Note: N = number of subjects; Range = range between minimal and maximum value; MIN = minimal value; MAX = maximum value; AM = arithmetic mean; SD = standard deviation. The acronyms of variables (test) are explained in the chapter Independent Variables Sample. As can be seen from Table 1, the ABMI values differ between the subjects, speci- fically for 10.3. Such a wide range can be explained by the age of the subjects, as they were born in 2001 or 2002. In this phase of the pre-puberty period, accelerated growth can occur in some individuals while physical development is slightly delayed in others. The results of the basic statistics of motor variables also show that the values for most of the motor skill variables are less scattered, which is mainly indicated by the low values of the standard deviation. A somewhat greater dispersion of results only can be detected in the MROSI variable (AM=1.5; SD=0.73) AMBI (body mass index) and performance (points) in the Rauch Cup. The calculation of the Pearson correlation coefficient showed that there is no stati- stically significant correlation between the number of points achieved and the ABMI variable. The correlation level is insignificant and negative (r = - 0.023). ANNALES KINESIOLOGIAE • 12 • 2021 • 2 109 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 Table 2. The Pearson correlation coefficient values between motor skill variables and performance (points) in the Rauch Cup. TEST POINTS MSKOK10 r .577** Sig. (2-‐tailed) .000 TESJCAS r -.106 Sig. (2-‐tailed) .552 MS20NVZP r .611** Sig. (2-‐tailed) .000 MT400 r -.513** Sig. (2-‐tailed) .002 MROSI r .259 Sig. (2-‐tailed) .139 SKI9 r -.477** Sig. (2-‐tailed) .004 TREAOPTO r -.161 Sig. (2-‐tailed) .362 Note: Sig. = statistical significance of correlation; ** = correlation is statistically significant at the risk level of 1%; r = Pearson correlation coefficient. Table 2 presents the Pearson correlation coefficients for motor space in relation to performance (points). It shows that there is a statistically significant correlation betwe- en the number of points achieved and the variables MSKOK10, MS20NVZP, MT400 and SKI9 at a risk level of 1%. In the cases of TREAOPTO, MROSI and TESJCAS, the calculation of correlation coefficients did not show a statistically significant correlation. 110 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Table 3. The result of the correlation of all anthropometric and motor skill variables with performance (points) in the Rauch Cup. R R2 Adjusted R2 Sig F .752a .566 .427 .003 Note: R = correlation coefficient; R2 = coefficient of determination; Adjusted R2: adjusted coef- ficient of determination; Sig F = statistical significance of correlation; a = predictors: constant (POINTS), ABMI, TREAOPTO, MROSI, TESJCAS, MT400, SKI9, MSKOK10. It is evident from Table 3 that the coefficient of multiple correlation is R = 0.752, indicating that the linear correlation between all variables and the criterion is high. The correlation between all variables and performance is statistically significant (Sig F = 0.003). The coefficient of determination is R2 = 0.566, which means that 56.6% of the performance variance can be explained by motor skill and anthropometric variables. Table 4: The result of the correlation between all motor skill variables and performance (points) in the Rauch Cup. R R2 Adjusted R2 Sig F .716a .512 .381 .005 Legend: R = correlation coefficient; R2 = coefficient of determination; Adjusted R2 = adjusted coefficient of determination; Sig F = statistical significance of correlation; a = predictors: con- stant (POINTS), TREAOPTO, MROSI, TESJCAS, MT400, SKI9, MSKOK10, MS20NVZP. The multiple correlation coefficient is R = 0.716, which indicates that a linear corre- lation between all motor skill variables at the same time and the criterion is high, as can be seen in Table 4. The correlation between all motor skill variables and performance is statistically significant (Sig F = 0.005). The coefficient of determination is R2 = 0.512, which means that 51.2% of the performance variance can be explained by motor skill variables. DISCUSSION Studies establishing a correlation between various dimensions of an athlete’s psychosomatic status and their performance undoubtedly represent the foundation for potential changes and qualitative improvement in various fields, especially concerning the successful and healthy development of an athlete. Since alpine skiing is a complex, ANNALES KINESIOLOGIAE • 12 • 2021 • 2 111 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 individual-structural sport, many different factors have an impact on the competitor. Success in this sport depends on an optimal combination of physical, psychological, and social dimensions. It is known that movement skills are the most reliable predictors of potential success, and anthropometric characteristics do not fall behind much in importance. Through a transformation process, we achieve changes in the psychosomatic status of the competitor. Because it is multidimensional and suprasummative (Petrović et al., 1983), a change in one factor causes a change in other factors. The level of the subjects’ development is substantially related to the competitive performance in the category of younger boys, because some of them experience accelerated growth of individual parts of the body at that age. This can have a positive as well as a negative effect on motor skills. Development in individuals may also be delayed, depriving them of movement skills, which can be particularly pronounced in sports. Petrović et al. (1983) state that the transformation process can have an inhibitory effect on certain abilities and charac- teristics during the growing-up phase. In the present study, we were interested in the direct correlations between motor skills and anthropometric characteristics and compe- titive performance for the category of younger boys in alpine skiing. The goal was to determine the correlation level between an individual motor skill and anthropometric variables and competitive performance as well as the impact of all selected motor skill and anthropometric variables on competitive performance. Further, we calculated the correlation between the entire set of motor skill varia- bles and the performance of the competitors at the Rauch Cup. During the analysis of the basic statistics, we determined that the Body Mass Index values vary considerably among the subjects, which is most likely the result of the already mentioned differen- ces in the stages of development. The calculation of the Pearson correlation coeffi- cient showed that the correlation between the Body Mass Index and performance is negligible (r = -0.023) and statistically insignificant, which confirms the assumptions regarding the differences in development in the considered age category. We found that in our sample the 20-meter sprint from a high start with legs parallel (MS20NVZP) is mostly related to competitive performance (r = 0.611) and that the correlation is stati- stically significant (Sig F = 0.000). The test assesses the basic movement ability of speed and is also mainly related to explosive power (acceleration at the start). A similar level of correlation (r = 0.577) and statistical significance (Sig F = 0.000) was achieved by the ten-jump test (MSKOK10). It indicates the repetitive explosive force as a manifestation of the energy component of power. Especially in slalom and giant slalom, this phenomenon is expressed when connecting relatively short turns and relying on repetitive power for speed control and (lateral) relief. The MT400 (r = -0.513) and SKI9 (r = -.477) tests, which are negatively correlated to competitive performance, revealed a statistically significant correlation. A 400-meter run expresses speed endurance, which is defined by the energy component of the move- ment and prevails in efforts of up to two minutes. The test is physiologically related to the duration of the activity on the track. SKI9 is the only test in our study that represents 112 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 special motor skills, i.e., agility, which is defined by rapid changes of direction as a manifestation of coordination. It is also defined by explosive power and speed (Petrović et al., 1983), which is also evident if we follow the course of the test. Among the pre- viously presented statistically characteristic correlations, SKI9 is the only variable that belongs to the subspace of the informational component of movement. Because it is a distinctly skiing test, we expected a similar result. The results of mo- tor skill tests and anthropometric measurements presented so far were not surprising. We find it all the more interesting that the correlation of the variable TESJCAS (squat jump on a tensiometer) is not statistically significant and that it stands in a negative, insignificant correlation with performance (r = -0.016). A particularly interesting fact is that we measured explosive thrust power with this test and expected higher corre- lation values, similar to those in the ten jumps test. The findings of this study do not comport with the findings of the study conducted by Lešnik and Žvan (2000), who found a statistical significance for two tests of explosive power (triple jump and stan- ding long jump), but for another generation of competitors. The balance and stability test (MROSI) revealed a low (r = 0.259) and statistically insignificant correlation with the criterion variable. Obviously, balance in the considered age categories does not yet affect performance, as can also be seen in the study by Lah (2014), who investigated the impact of balance between the categories of younger and older boys and girls on the performance in alpine skiing. The correlations were insignificant for all four groups of subjects. The last studied test of motor skill dimensions was a squat jump between the bars of the OPTOJUMP device (TREAOPTO), which was defined by reaction speed. It revealed a negligible negative correlation (r = -0.161) and statistical insignificance. For the entire set of all studied variables, we found that there is a statistically significant correlation (Sig F = 0.003) with performance at the competition (R = 0.752). The coef- ficient of determination was R2 = 0.566, which means that 56.6% of the performance variance can be explained by motor and anthropometric variables. The set of all motor variables, which we additionally calculated, is statistically significantly correlated (Sig F = 0.005) with competitive performance (R = 0.716). We were therefore able to expla- in the 51.2% of the performance variance with motor skills variables (R2 = 0.512), which represents a slightly smaller share than for the set of all variables. From the obtained results of the set of all variables and set of motor skill variables, we can conclude that the Body Mass Index (ABMI) itself is not statistically significan- tly related to the points; however, as a whole (together with the motor skill variables) it clearly contributes to the proportion of explained variance. The present study rebutted the findings of Lah (2014), who determined a weak and uncharacteristic correlation between balance (MROSI) and competitive performance. For the variable TREAOPTO (reaction speed), and especially for the variable TESJ- CAS (explosive power), we expected higher correlation values and statistical signi- ficance. However, the results of the basic statistics of these three dimensions varied considerably, which we tried to explain with the differences in the development level of the studied age category and with the assumption that not all competitors have the same predispositions, opportunities and desire for successful participation in top alpine ANNALES KINESIOLOGIAE • 12 • 2021 • 2 113 Stojan PUHALJ, Blaž LEŠNIK, Alexander POVHE, Robi KELC, Črtomir MATEJEK: CORRELATIONS BETWEEN MOTOR ..., 103–115 skiing. Since the sample represented an already selected population, De Costa (2009) similarly drew attention to the fact that currently children are directed to alpine skiing based on social criteria and increasingly less on motor skill criteria. To consider theory and practice, it can be said that the findings of the present study represent a foundation for further research, as balance, reaction speed and explosive thrust tests did not show any statistical significance. In their study, Bandalo and Lešnik (2011) proposed to reduce the number of variables from the battery of tests for determi- ning motor skills and anthropometric characteristics in the future. We support this idea; however, in the future, regular studies in this field are required to determine important motor and anthropometric dimensions and tests, because Bandalo and Lešnik (2012) established in their study that over a period of four years (2007 to 2010) the correlation between anthropometric and motor skill variables and performance varied. CONCLUSION We established a statistically significant value of the multiple correlation coefficient (R = 0.752), which means that 56.6% of the variance of the actual performance can be explained by the considered motor skill and anthropometric variables (R2 = 0.566). Today’s (sedentary) lifestyle and greater involvement of young people in other non- -sport fields, together with the relatively high costs of skiing and ski training, which often do not allow the parents to enroll their children in ski schools, result in a funda- mentally limited selection process. We will not change this fact with our research, but we can conclude that not all competitors who were the subjects of measurement at the Faculty of Sports are part of the skiing circuit on account of extremely positive physical reasons. On the other hand, having considered a sample of younger boys, we can conclude that the stage of development plays an important role in the separation of the physi- cally more successful from the physically disadvantaged competitors. Therefore, it is necessary to pay special attention to the latter in terms of social and psychological support. We have proposed the idea of managing the mentioned groups of competitors separately during the transformation process, although it is clear that in practice this may be problematic. Undoubtedly, with a proper mindset and efforts we can ensure less discomfort or neglect among young ambitious competitors. In the future, it will be necessary to monitor the development of young athletes even more systematically. 12 - 13 years is a sensitive period, which is why it is all the more important that the battery of tests is effective and provides information about the athlete necessary for the professionals in the field to guide them properly during the training process. The fact remains that many other areas contribute to competitive performance, such as psychological preparation, personality traits, as well as tactical preparation. 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D., Ciolpan, P., Roman, I., Muresan, A. & Grosu, E. F. (2019). Dynamics of salivary cortisol and testosterone during competition stress in alpine skiing in adults and children. Cognition, Brain, Behavior. An Interdisciplinary Journal 23(1) 29-41. https://doi.org/10.24193/cbb.2019.23.02. ANNALES KINESIOLOGIAE • 12 • 2021 • 2 117 Original scientific article DOI: https://doi.org/10.35469/ak.2021.326 received: 2022-05-25 UDC: 612.741:796.012 TIME PASSES – HEALTHY HABITS STAY? A LONGITUDINAL SMALL SAMPLE COMPARISON OF MUSCLE CONTRACTILE PROPERTIES, MOTOR ABILITIES AND LIFESTYLE CHARACTERISTICS OF ATHLETES AND NON-ATHLETES Saša PIŠOT1, Rado PIŠOT1, Boštjan ŠIMUNIČ1 1 Science and Research Centre Koper, Slovenia Corresponding author: Saša PIŠOT Science and Research Centre Koper, Garibaldijeva 1, 6000 Koper, Slovenia Tel.: +386 5 663 77 00 e-mail: sasa.pisot@zrs-kp.si ABSTRACT Introduction: Because healthy behaviors learned early in life are more likely to be maintained during adulthood, we aimed to investigate longitudinal changes of partici- pants that were regularly involved in extracurricular sport activities (athletes; N = 7; 4 boys) and those that were not (non-athletes, N = 6; 3 boys) Methods: Participants of both groups were invited for re-assessment at the age of 27, in 2019, 12 years after they participated in a 5-year longitudinal study as adoles- cents (9–14 years of age, in the period 2001‒07). We investigated vastus lateralis (VL) and biceps femoris (BF) contractile properties (tensiomyography), maximal running speed (photocells), anthropometric measures (bioimpedance), maximal vertical jump- ing height (squat and countermovement jumps on a ground reaction force plate), and lifestyle characteristics (GPAQ and EHIS surveys). Results: Based on Cohen’s d effect size we found that athletes have lower body mass index, higher maximal running speed, better maximal vertical jumping height, and shorter BF contraction time, not found in VL, compared to non-athletes. Further- more, athletes also exhibit healthier lifestyle characteristics such as lower sedentary time and higher daily energy expenditure than non-athletes. Athletes follow diet regi- mens consisting of more regular meals with more protein and indulge less in health-risk behavior (smoking and alcohol consumption). However, the self-perception of health and quality of life was lower in athletes than in non-athletes. Conclusion: EU regulations and the beginning of the COVID-19 pandemics pre- vented us from conducting a study on a more representative sample. Nevertheless, we could confirm that regular sport participation yields better physical performance 118 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 and a healthier lifestyle but could also have a negative impact on health (injuries) and quality of life. Keywords: motor development, tensiomyography, sport, physical exercise, healthy lifestyle ČAS MINEVA - ZDRAVE NAVADE OSTANEJO? LONGITUDINALNA PRIMERJAVA KONTRAKTILNIH LASTNOSTI MIŠIC, GIBALNIH SPOSOBNOSTI IN ZNAČILNOSTI ŽIVLJENJSKEGA SLOGA ŠPORTNIKOV IN NEŠPORTNIKOV NA MAJHNEM VZORCU IZVLEČEK Uvod: Namen raziskave je ugotoviti longitudinalne spremembe v skupini preisko- vancev, ki so se redno ukvarjali z obšolskimi športnimi dejavnostmi (skupina športni- kov; N = 7, 4 dečki), in tistih, ki se niso kontinuirano ukvarjali s športom (skupina nešportnikov, N = 6, 3 dečki). Metode: Udeleženci obeh skupin so bili povabljeni na ponovne meritve pri starosti 27 let, leta 2019, torej 12 let po tem, ko so bili v starosti od 9-14 let, v obdobju 2001- 2007 vključeni v petletno longitudinalno študijo. Preučevali smo kontraktilne lastnosti mišic: vastus lateralis (VL) in biceps femoris (BF) (z metodo tenziomiografije), hitrost sprinta z letečim štartom (s fotokamerami), antropometrične podatke (z bioimpedan- co), dosežek navpičnega skoka (skoki na tenziometrijski plošči s pomočjo in brez pomo- či rok) ter nekatere značilnosti življenjskega sloga (anketi GPAQ in EHIS). Rezultati: Na podlagi velikosti učinka (Cohenove d) smo ugotovili, da imajo špor- tniki v primerjavi z nešportniki nižji indeks telesne mase, večjo hitrost teka, boljšo zmo- gljivost vertikalnih skokov in krajši čas krčenja BF, kar pri VL nismo ugotovili. Poleg tega imajo športniki tudi bolj zdrave vzorce življenjskega sloga, manj sedijo in več gibajo (večja dnevna poraba energije) kot nešportniki. Nadalje prehrano športnikov sestavljajo bolj redni obroki z več beljakovinami, poleg tega imajo manj zdravju ne- varnih praks (kajenje in uživanje alkohola). Kljub temu pa so športniki svoje zdravje in kakovost življenja ocenili nižje kot nešportniki. Zaključek: Regulativni predpisi EU za področje varovanja osebnih podatkov (GDPR) kot tudi začetek pandemije COVID-19 so nas pri izvedbi študije na bolj repre- zentativnem vzorcu močno ovirali. Kljub temu smo lahko potrdili, da redno ukvarjanje s športom ohranja boljšo telesno zmogljivost, bolj zdrav življenjski slog, kar pa lahko vpliva na zdravje (poškodbe) in kakovost življenja. Ključne besede: gibalni razvoj, tenziomiografija, šport, gibalna aktivnost, zdrav življenjski slog 119 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 INTRODUCTION Most research into healthy behavior and predictors of these behaviors generally focuses on individuals’ incentives to adopt positive health practices at a single point in time and do not provide a framework for how healthy behaviors may change over time. Frech (2012) indicates several reasons to investigate how and why engagement in healthy behavior changes across pivotal life course stages (Frech, 2012). First, be- cause healthy behaviors learned early in life are more likely to be maintained during adulthood (Lau, Quadrel, & Hartman, 1990; Telama et al., 1997) and because health- promoting behaviors aid in preventing or delaying chronic or life-threatening disease. And secondly, to evaluate whether personal and social resources at one life course stage (for example during adolescence) exert an enduring or cumulative impact on healthy behaviors at later life course stages. Therefore, sport and sport participation are viewed as an effective activity for solv- ing problems and improving quality of life for individuals and society alike. Not just for increasing self-confidence, self-esteem, and positive body image, building our charac- ter in the form of discipline, teamwork, and responsibility, as well as our importance, but also creating motor and sport-specific skills convertible into physical capital and improving health, fitness, and an overall sense of physical well-being (Coakley, 2011). Researchers have given considerable attention to the athlete development process, e.g., positive youth development through sport (Holt, 2008). Utilization of skeletal mus- cle mass to produce power is of great importance in sport. However, skeletal muscle is also indispensable for locomotion, maintenance of body posture, thermoregulation, sugar and lipid metabolism and, therefore, for general health. To realize locomotion, the muscles must produce power by generating force and shortening velocity at the same time. The speed of muscle contraction is largely determined by fiber type composition. In children, knowing the fiber type composition may be used to help in formulating an informed decision regarding taking up a sport in which the child most likely will excel. While there are numerous data on the fiber type composition of various skeletal muscle in adults and adolescents, we are aware of only seven cross-sectional studies on the fiber type composition of muscle in children between the ages of 2 months and 11 years (Bell, MacDougall, Billeter, & Howald, 1980; Glenmark, Hedberg, & Jansson, 1992; Kriketos et al., 1997; Lexell, Sjöström, Nordlund, & Taylor, 1992; Lundberg, Eriksson, & Mellgren, 1979; Österlund, Thornell, & Eriksson, 2011; Verdijk et al., 2014). Furthermore, only one study presented longitudinal data of VL composition from adolescence to adulthood (Glenmark et al., 1992) and found lower proportion of slow twitch fibers in VL muscle in girls at the age of 16 and the opposite at the age of 27. Especially where it is very difficult, for ethical reasons, to invasively measure skel- etal muscle myosin heavy chain proportion or fiber type composition, tensiomyography (TMG) provides non-invasive information on changes in functional skeletal properties (Valenčič & Knez, 1997). Specifically, it was established that TMG-derived contraction time (Tc) could be used to non-invasively estimate skeletal muscle MHC type 1 propor- tion (Šimunič, Degens, & Rittweger, 2011). 120 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 In the period 2002‒07 we followed with TMG screening >300 children in six yearly assessments. Approximately one third (107) were measured on all occasions and ana- lyzed (Pišot et al., 2004; Šimunič et al., 2017; Završnik et al., 2016; Završnik, Pišot, Šimunič, Kokol, & Blažun Vošner, 2017). Briefly, we found that boys in general had slower muscles than girls. During early maturation in the VL muscle there is a slow-to- fast transition that begins between 6 and 10 years of age, which then appears to stabilize to adult proportions. Regular participation in sport was associated with a faster biceps femoris (BF), but not in VL, for both sexes (Šimunič et al., 2017). We also found cor- relation between muscle contractile properties and the running speed that was biased for both sexes. Specifically, the running speed was less correlated with VL Tc in boys than in girls. However, boys’ running speed was more correlated with BF Tc than in girls (Završnik et al., 2016, 2017). Our data thus represent a first non-invasive, if indi- rect, indication of developmental trends in changes in muscle fiber type composition in children. The most interesting finding for us was that regular sport participation in children aged between 9 and 14, compared to children without any extracurricular sport par- ticipation, impacted Tc in non-gravitational BF muscle but not gravitational VL mus- cle, in both sexes (Šimunič et al., 2017). However, it remains to be seen whether the continuation of exercise (sport participation) through adolescence to adulthood could further impact Tc in both muscles. Even more, it would be interesting to see the effect of continued sport participation on motor abilities, body characteristics and main char- acteristics of healthy lifestyle (nutrition, PA, habits) in the later adolescence and early adulthood of participants. After carrying out a 5-year longitudinal monitoring of skeletal muscle contractile properties and motor abilities in >300 children within two consecutive research pro- jects: (i) “The role of biomechanical properties of skeletal muscle in the motor devel- opment of children”, 2001‒04; and (ii) “Monitoring of changes in skeletal muscle bio- mechanical characteristics in early childhood and adolescence”, 2004‒07, we invited those same subjects for a follow-up assessment in 2019 with the purpose of longitudi- nally investigate the changes in skeletal muscle contractile properties, physical activity level, nutrition, and health related habits. METHODS In previous analyses we investigated motor abilities development in 9‒14 year-old children as a factor of sex and sport participation. Furthermore, in 2019 we invited the subjects to participate again (12 years later), taking the same measurements. Further- more, at the final assessment we investigated basic lifestyle characteristics which we obtained by a questionnaire including demographic data, physical activity, nutrition and smoking habits. Additionally, the participants were asked about their participation in organized sports, their sport injury history and important life stress events. Results of the first six assessments of vastus lateralis (VL) and biceps femoris (BF) contractile 121 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 properties (tensiomyography), flying running speed (photocells), anthropometric meas- ures (bioimpedance), and vertical jumping performance (squat and countermovement jumps on a ground reaction force plate) were previously reported in four scientific publications (Pišot et al., 2004; Šimunič et al., 2017; Završnik et al., 2016, 2017). This manuscript presents data from a 12-year follow-up in a subsample of the same partici- pants. Participants and recruitment During the recruitment we focused on inviting the 107 participants who were consistently present for all six annual measurements during the 2002‒07 period. The participants came from the Slovene towns of Koper, Izola, Piran, Ljubljana, and Mar- ibor. Due to strict personal data protection legislation (EU 2016/679, General Data Protection - GDPR), we had many problems in re-establishing contacts to recruit participants for follow-up measurements, as we only had a database with the first and last names and their elementary school. The principals of the elementary schools could not provide us with the subjects’ contact information, so we had to resort to the “snowball” method and social media. We searched for potential acquaintances to contact the participants and after they agreed to be contacted, we invited them to participate in the follow-up. This was usually done through their social media (Facebook and Instagram) or by a phone call. In addition, our research organization advertised the invitation to participate in the follow-up through various media (of- ficial website, Facebook). Despite an enormous amount of time and effort invested, we kept receiving responses of interested candidates, but mostly ones who had not participated in our previous measurements from 2002‒07 and thus were not eligible for the follow-up. Over the course of about six months, we were able to recruit 13 participants. We divided these participants into two groups: a group of athletes, who had regularly participated in organized sport activities during the past 12 years (ath- letes; N = 7; 4 boys) and non-athletes (N = 6; 3 boys). Specifically, it was evident from their questionnaire data that seven of them continuously participated in various sports from the age of 9 to 25 and were classified as athletes, while six of them had not participated in any sports for at least the past 10 years (non-athletes), although five of them had been active during the period of primary school. Table 1 summarizes the proportion of those involved in organized sport activities in three age-periods for both studied groups. 122 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Table 1: Proportion of participants’ sport participation in the two studied groups: (i) those who continuously practiced sport from 14 to 26 years of age (athletes); and (ii) those who did not practice sport at all or only until they were 16 years old (non- athletes). Athletes Non-athletes N 7 6 Sport participation in the age period of 9‒14 5 out of 7 5 out of 6 Sport participation in the age period of 14-16 7 out of 7 2 out of 6 Sport participation in the age period of 16-26 7 out of 7 0 out of 6 Measurement procedures The follow-up measurements consisted of the following test battery: arm strength (dominant hand compression - dynamometer), TMG of two muscles, maximal running speed (7-meter sprint with flying start), maximal vertical jump height, body height, mass, mass index, and composition measurement (fat mass, muscle mass). After the tests, each subject was asked to complete a specific questionnaire consisting of several sets of validated questions (GPAQ, EHIS) to provide data on their current PA status, injury history, health status, and lifestyle to allow capturing possible factors that might influence general fitness (biomechanical muscle characteristics) at each stage of the subject’s life (high school, university, and current age). Tensiomyography (TMG) The TMG method measured the contractile properties of two skeletal muscles in the dominant site (vastus lateralis – VL, and biceps femoris – BF). Each muscle was stimu- lated with single electric pulses, rectangular in shape, lasting 1 ms. The pulse amplitude was gradually increased until the maximum response was obtained. We saved the two largest responses for further processing and took the average of both for further analy- ses. We calculated two contractile parameters for each response: a maximal amplitude (Dm, in mm) to be used for the calculation of contraction time (Tc, in ms) between 10 % to 90 % Dm. 123 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 Measurement of body composition After body mass and height were measured, body mass index was calculated, and composition was measured using a bioimpedance meter (Maltron BioScan 916s, UK). We ensured that participants were calm, normally hydrated, and rested for at least 20 minutes before the measurement. Fat mass was measured via a 4-point measurement. Maximal running speed After a standardized 10-minute warm-up, the maximal running speed was measured with a flying start over a distance of 7 meters. We assured plenty of room to accelerate and decelerate before and after assessment gates (Powertimer 300, Newtest, Finland), respectively. Each participant made three attempts and the best result was taken for further analysis. Maximal vertical jumping height We measured the height of the vertical jump without using hands (hands on the hips). Each participant performed three countermovement and three squat jumps on a ground reaction force plate (Quattro jump 9290AD, Kistler Ltd., Austria). The best result was taken for further analysis. Questionnaire The questionnaire designed for this study consisted of several sets of validated questions and covered basic socio-demographic data, health status and nutrition, physical/sport activity, and aspects of sedentary time. We used an adapted part of the European Health Interview survey – EHIS to assess eating habits (regular diet, type of diet) and indicators of quality of life. Additionally, physical/sport activity was assessed by a self-reported validated questionnaire The Global Physical Activity Questionnaire – GPAQ (Armstrong & Bull, 2006). Statistics Due to the small sample size, we did not perform classical parametric statistical analysis. We performed the non-parametric Mann-Whitney test to compare athletes vs. non-athletes only for indicative purposes. Since small samples yield low statisti- cal power and only large effects will end up significant, we rather calculated effect sizes – Cohen’s d values ‒ and interpreted main findings based on the effect size (low 124 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 < 0.20; moderate 0.20 ≤ Cohen’s d < 0.8 and high ≥ 0.8). For comparing correlations between lifestyle characteristics and motor abilities and muscle characteristics, we used the Spearman rho coefficient indicating significant correlations at p < 0.05. RESULTS We were able to repeat the longitudinal monitoring of the biomechanical character- istics of skeletal muscle only on a sample of 13 (7 male) participants at the age of 27 years: 4 participants from Maribor, and 9 from Koper over 7 testing days executed in January, February, and October 2019. In all comparisons there were no statistical differences confirmed by the Mann- Whitney test; however, due to lower sensitivity of statistical tests in very small samples, we interpreted effect sizes. Table 2 shows a progressive trend in basic anthropometric data of pooled participants indicating normal growth. When comparing athletes and non-athletes (Table 4), we found that athletes had moderately to significantly lower body mass index (effect size from 0.42 to 1.07) throughout the whole period and lower fat mass (effect size 0.65) at the age of 27 years. This is consistent with lesser sedentary time (effect size 0.55) and higher daily energy consumption (effect size 0.47) compared to non-athletes. Table 3 presents motor abilities in pooled participants. When compar- ing athletes and non-athletes (Table 4), we could not confirm higher running speed in athletes throughout all periods. However, countermovement and squat jump heights were higher in athletes when compared to non-athletes at the age of 27 (effect size 0.81 and 0.74, respectively). VL Tc was not lower in athletes; it was, however, lower in BF with the largest effect size at the age of 27 years (0.64). Table 2. Basic anthropometric data of pooled participants. Age 9 years 10 years 11 years 12 years 13 years 14 years … 27 years N 13 13 13 13 13 13 … 13 Body mass index / kg/m2 17.1 ± 2.5 17.9 ± 2.6 18.0 ± 2.9 19.5 ± 3.0 20.0 ± 2.7 20.3 ± 2.4 … 22.8 ± 3.3 Body height / m 1.41 ± .06 1.45 ± .07 1.49 ± .07 1.58 ± .07 1.65 ± .08 1.69 ± .08 1.76 ± .09 Body mass / kg 34.3 ± 7.0 37.9 ± 8.2 40.4 ± 9.1 48.9 ± .11 54.8 ± 10.7 58.2 ± 9.7 71.6 ± 14.4 125 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 Table 3. Pooled data of selected motor abilities. Age 9 years 10 years 11 years 12 years 13 years 14 years … 27 years N 13 13 13 13 13 13 … 13 Running Speed / m/s 5.6 ± 0.5 5.6 ± 0.4 5.7 ± 0.4 6.0 ± 0.4 6.3 ± 0.8 6.2 ± 0.4 … 6.4 ± 0.5 CMJ height / cm - - - - - - … 29.8 ± 5.6 Squat jump height / cm - - - - - - … 28.3 ± 5.2 CMJ – countermovement jump Table 4. Comparison between athletes and non-athletes Group Athletes Non-athletes Effect size* Number 7 6 Body mass index / kg/m2 9 years 16.7 ± 2.9 17.7 ± 1.9 0.54 10 years 17.3 ± 3.0 18.7 ± 2.2 0.63 11 years 17.4 ± 2.9 18.7 ± 2.9 0.48 12 years 18.7 ± 3.1 21.0 ± 2.4 0.98 13 years 19.4 ± 3.3 20.7 ± 1.8 1.07 14 years 19.9 ± 2.7 20.8 ± 2.0 0.42 … … … … 27 years 21.9 ± 3.7 23.1 ± 2.5 0.65 Fat mass / % 27 years 22.7 ± 6.4 23.7 ± 3.0 0.33 Running speed / m/s 9 years 5.5 ± 0.4 5.7 ± 0.5 -0.39 10 years 5.7 ± 0.4 5.6 ± 0.4 -0.15 11 years 5.6 ± 0.4 5.7 ± 0.4 -0.41 12 years 5.9 ± 0.4 6.0 ± 0.4 -0.02 13 years 6.0 ± 0.3 6.1 ± 0.3 -0.39 14 years 6.1 ± 0.4 6.3 ± 0.3 -0.64 … … … … 27 years 6.4 ± 0.5 6.3 ± 0.5 0.31 126 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Group Athletes Non-athletes Effect size* Number 7 6 Countermovement jump height / cm 27 years 31.6 ± 5.7 27.6 ± 5.0 0.81 Squat jump height / cm 27 years 29.9 ± 5.3 26.1 ± 7.2 0.74 Contraction time of vastus lateralis / ms 9 years 20.7 ± 2.5 19.2 ± 2.6 -0.57 10 years 19.0 ± 2.1 17.6 ± 2.1 -0.64 11 years 19.3 ± 4.2 19.2 ± 2.8 -0.01 12 years 21.7 ± 4.4 20.4 ± 2.3 -0.56 13 years 21.6 ± 3.6 22.1 ± 2.4 0.22 14 years 22.7 ± 3.7 23.7 ± 3.3 0.30 … … … … 27 years 21.5 ± 3.0 21.4 ± 2.2 -0.05 Contraction time of biceps femoris / ms 9 years 32.1 ± 3.5 34.2 ± 7.3 0.29 10 years 31.2 ± 2.9 32.8 ± 9.1 0.17 11 years 32.0 ± 3.5 33.9 ± 6.6 0.29 12 years 31.1 ± 4.5 33.3 ± 8.6 0.26 13 years 29.4 ± 3.7 36.9 ± 13.0 0.58 14 years 29.6 ± 1.8 34.9 ± 12.8 0.41 … … … … 27 years 29.1 ± 2.8 33.9 ± 7.6 0.64 Sedentary time / min 27 years 335 ± 157 417 ± 147 0.55 Daily energy consumption / MET 27 years 4663 ± 2823 3346 ± 2780 0.47 MET… metabolic equivalent; *positive values of effect size denote better results for athletes. Data from GPAQ showed higher daily energy consumption (MET) because of sport participation of athletes in parallel to lower daily sedentary time than in non-athletes. Even more, sedentary time at age of 27 years correlates negatively with body mass index (r = −0.47) and fat mass (r = -0.59), and positively with BF Tc at this same age (r = 0.50). 127 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 Additionally, the differences in certain socio-demographic factors and lifestyle characteristics between athletes and non-athletes were examined, which are shown in Table 5. Table 5: Comparison of some lifestyle characteristics of athletes and non-athletes Group Athletes Non-athletes Effect size* N 7 6 Self-assessment of…: General health status 3.8 ± 0.6 4.2 ± 0.6 0.67 Physical capability 3.3 ±0.7 3.3 ±0.9 0.00 Psychological status 3.8 ±0.6 3.8 ±0.6 0.00 General quality of life 3.8 ±0.6 4.2 ±0.3 1.33 Eating habits Breakfast 5.7 ±0.67 4.0 ±1.9 0.89 Morning snack 3.2 ± 1.0 2.4 ± 1.6 0.50 Lunch 5.5 ±0.7 5.8 ±0.3 1.00 Afternoon snack 3.3 ± 1.6 2.5 ±1.0 0.80 Dinner 5.2 ±1.4 5.5 ±0.7 0.43 Food consumption Whole-grain bread 4.0 ± 1.2 4.3 ± 2.0 0.15 Olive oil 4.3 ± 1.3 5.8 ± 1.0 1.50 Milk and low-fat dairy 3.8 ± 1.2 4.8 ± 2.0 0.50 Cottage cheese, yogurt, cheese 4.2 ± 1.5 4.3 ± 2.0 0.05 Dark chocolate 2.3 ± 1.3 2.0 ± 0.9 0.33 Meat products 3.7 ± 1.2 2.0 ± 1.3 1.31 Red meat 2.8 ± 1.2 3.0 ± 1.3 0.15 Poultry 3.8 ± 1.2 2.5 ± 1.4 0.93 Bacon 2.0 ± 0.9 2.3 ± 1.2 0.25 Fish 2.7 ± 1.0 2.3 ± 0.7 0.57 Fizzy and non-fizzy non-alcoholic drinks 3.0 ± 1.0 3.8 ± 2.2 0.36 Alcohol beverages 2.3 ± 0.4 3.7 ± 0.9 1.56 Fried dishes 2.8 ± 1.0 3.3 ± 1.2 0.42 * effect sizes are presented as absolute values. 128 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 A noticeable difference between the groups was that athletes reported predominant- ly standing (physical work) while non-athletes, all but one, reported predominantly sedentary work. There were no differences between athletes and non-athletes in terms of subjective assessment of physical fitness, mental well-being, and health concerns, but interestingly athletes rated their general health (effect size 0.67) and their overall quality of life (effect size 1.33) lower than did non-athletes. Much of the difference between the groups was reflected in eating habits, with ath- letes eating more regularly and skipping breakfast and afternoon snack less often (ef- fect sizes 0.89 and from 0.50 to 0.80, respectively) than non-athletes. In terms of food choices athletes are more likely to eat meat products (effect size 1.31), especially poul- try (effect size 0.93). Non-athletes, on the other hand, are more likely to consume olive oil (effect size 1.50) and alcoholic beverages (effect size 1.56). DISCUSSION Based on effect sizes, due to low number of participants, we could conclude that at the age of 27 years athletes had lower body mass index, fat mass, sedentary time, BF Tc and higher running speed, countermovement and squat jump heights and daily energy consumption when compared to non-athletes. Similar trends as at 27 years were also found in the age period from 9 to 14 years, but only for two abovementioned lon- gitudinal variables: body mass index and BF Tc. Interestingly, only running speed was at 9‒14 years lower in athletes than in non-athletes, the opposite as at 27 years. At the age of 27, the largest effect size was recorded for countermovement jump height, squat jump height, body mass index, and BF Tc (effect sizes > 0.60). This is the first study to collect 18 years of longitudinal data on TMG parameters from childhood to adulthood. We have previously reported that children’s regular par- ticipation in sports was associated with shorter BF Tc, but not with VL Tc, as found here. More specifically, BF Tc differences were observed between sedentary and ath- letic groups in boys and girls and were significant at 12 years of age (Šimunič et al., 2017). As this sample was a sub-sample of the previous study a similar result could be confirmed for the period of 9-14 years. However, this trend was maintained or even slightly increased with regular sport exercise until the age of 27 years. Although short Tc was confirmed in BF it was not the case for VL Tc, which seems to be independent from regular exercise. A similar situation was observed in adult track and field sprint- ers where sport participation resulted in a higher proportion of type IIc fibers in the BF, which was also associated with a lower BF Tc (19.5 vs. 30.2 ms in sprinters vs. sedentary subjects, respectively) (Dahmane, Djordjevič, & Smerdu, 2006). It could be that the habitual loading of weight-bearing muscles (as for VL) through normal daily physical activity is already relatively high in non-athletes and that the non-weight bear- ing muscles are more heavily loaded during exercise (Šimunič et al., 2017). If so, this may explain the grater adaptation to regular exercise in BF than in VL. Our group of athletes consisted of three handball players, two volleyball players, one dancer and one 129 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 multisport athlete. When we compare their average BF Tc’s at the age of 27 years (29.6 ms) with the averages of other groups of adult athletes, e.g., male sprinters at 19 ms (Šimunič et al., 2017), beach volleyball players at 25 ms (Rodríguez Ruiz et al., 2012), gymnasts at 27 ms (Šimunič et al., 2017), and football players at 28 ms (Rey, Lago- Peñas, Lago-Ballesteros, & Casáis, 2012) they have a longer BF Tc, but a shorter BF Tc than non-athletes with 32 ms (Šimunič, 2012; Šimunič, Pišot, Rittweger, & Degens, 2018). Thus it appears that participation in sports during childhood may lead to a faster profile of BF Tc, an important muscle for fast explosive sports such as football, vol- leyball, sprinting, and gymnastics as well as for overall knee health (Biscarini, Botti, & Pettorossi, 2013; Guelich, Xu, Koh, Nuber, & Zhang, 2016). To support this, we have previously reported that children who regularly participate in sports also have higher running speed (Volmut, Pišot, & Šimunič, 2016) and that this was negatively correlated with BF Tc (Pišot et al., 2004; Završnik et al., 2016) - but only in boys beyond the age of 13 years. And indeed, we were able to confirm higher sprinting velocity in athletes only at the age of 27 years, and not before, as five of the six participants in the non- athlete group also practiced sports during the age period of 9‒14 years. For all other non-longitudinal variables of body composition and muscle perfor- mance, which were not assessed until age 27, differences between the two groups were in favor of the athletes. Specifically, athletes had lower fat mass, which is indicative of a lower body mass index, and had higher jumping performance, an indicator of over- all body strength. Regarding lifestyle variables, athletes had lower sedentary time and higher daily energy consumption. Although we have found moderately lower sedentary time in athletes, when compared to non-athletes, it is not always so, as previous studies reported that athletes can be highly active and have high sedentary time, because of an independent relationship between moderate-to-vigorous physical activity time and sit- ting time (Swartzendruber, Croteau, & Maine, 2020; Weiler, Aggio, Hamer, Taylor, & Kumar, 2015). The relationship among high sedentary time for athletes’ health, risk of cardiovascular and metabolic diseases, despite high activity level, remains to be seen. In their self-reporting, athletes rated their health and quality of life worse than did non-athletes. Although their health status did not reflect any serious medical condition or show any chronic diseases, we can speculate that athletes report lower QoL due to their recent injury experience as these lower scores primarily affect social and global functioning, suggesting that they feel that their injuries limit their ability to participate in sports and social life (McGuine, Winterstein, Carr, Hetzel, & Scott, 2012; Valovich McLeod, Bay, Parsons, Sauers, & Snyder, 2009). It is also evident that athletes eat more regularly, place more emphasis on breakfast, eat healthy snacks with higher in- take of animal-sourced protein, and consume less fats and less alcohol. Our findings are consistent with adolescent athletes eating healthier and having more varied diets (von Rosen, Olofsson, Väsbom, & Heijne, 2019). The major limitation of the study was the small sample number and low response rate of participants for re-testing (11 %). This is a major shortcoming of all longitudinal studies due to the EU regulation of personal data protection, disinterest of participants in attending the later measurements, and certainly in this case the COVID-19 pandem- 130 Saša PIŠOT, Rado PIŠOT, Boštjan ŠIMUNIČ: TIME PASSES – HEALTHY HABITS STAY? ..., 117–133 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 ics. Furthermore, we had both sexes in both groups but of similar distribution. There- fore, we have done only effect size estimation without statistical hypothesis testing. CONCLUSION Despite the small sample we can identify a trend which confirms that many years of sports participation and regular exercise have positive effects on physical fitness and motor abilities, and especially on the contractile properties of the skeletal muscles. Athletes have lower body mass index, exhibit greater running speed, better jumping performance and shorter contraction time of the posterior thigh muscle. Athletes also spent less time sitting and have higher daily energy expenditure than non-athletes, but this was not reflected on fat mass. The contraction time of the anterior thigh muscles, which did not differ between the groups, confirms our previous findings that the daily stimulus of the postural muscles is large enough to maintain contractile properties, which is not the case for the posterior thigh muscles, which are less used during daily tasks. We also found healthier lifestyle habits in athletes. They practice healthier diet regimes with more regular meals containing more protein (meat products, poultry) as well as fewer health-risk practices (smoking and alcohol consumption); regarding the self-assessed quality of life, athletes reported lower health status and general quality of life, which can be explained by the reported injuries and strict sport regimes of athletes. 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New York: Nova Science Publishers. von Rosen, P., Olofsson, O., Väsbom, S., & Heijne, A. (2019). Correlates of health in adolescent elite athletes and adolescents: A cross-sectional study of 1016 adolescents. European Journal of Sport Science, 19(5), 707–716. https://doi.org/10.1080/17461391 .2018.1552721. Weiler, R., Aggio, D., Hamer, M., Taylor, T., & Kumar, B. (2015). Sedentary behaviour among elite professional footballers: health and performance implications. BMJ Open Sport & Exercise Medicine, 1, e000023. https://doi.org/10.1136/bmjsem-2015-000023. Završnik, J., Pišot, R., Šimunič, B., Kokol, P., & Blažun Vošner, H. (2017). Biomechani- cal characteristics of skeletal muscles and associations between running speed and con- traction time in 8- to 13-year-old children. Journal of International Medical Research, 45(1), 231–245. https://doi.org/10.1177/0300060516687212. Završnik, J., Pišot, R., Volmut, T., Koren, K., Blažun Vošner, H., Kokol, P., Vošner, J., & Šimunič, B. (2016). Lower correlation between biceps femoris contraction time and maximal running speed in children than in adults: a longitudinal study in 9- to 14-year old children. Annales Kinesiologiae, 7(1), 21–42. http://ojs.zrs-kp.si/index.php/AK/ar- ticle/view/112. REPORTS AND REVIEWS POROČILA IN OCENE ANNALES KINESIOLOGIAE • 12 • 2021 • 2 137 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 11th INTERNATIONAL SCIENTIFIC AND PROFESSIONAL CONFERENCE “A CHILD IN MOTION” Portorož, Slovenia, 4‒6 October 2021 In the two years that had passed since our previous conference, we overcame a pe- riod of lockdowns when it was at times difficult to follow and adapt to all the new rules of work and communication, but despite the new “reality,” science and practice met at the 11th International Scientific and Professional Conference “A Child in Motion.” This time the working title of the conference, “The lockdown aftermath,” suggested what we had experienced missed and learned during this period. We analyzed topics engendered by this situation in scientific and professional language, again enjoying the hospitality of the Grand Hotel Bernardin and the towns of Portorož and Piran. The two-day program offered 3 plenary lectures and 11 keynote speakers who pre- sented current research from the educational, paediatric, kinesiology, physiological, 138 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 socio-psychological, and nutritional fields on the impact of the COVID-19 pandemic on children. Prominent speakers highlighted current evidence on child well-being in the aftermath of the pandemic. The “Book of Proceedings” contains 35 scientific and 121 professional papers by more than 200 authors and co-authors from over a dozen European countries. The pa- pers present current research findings as well as examples of best practices by teachers and educators in addressing the challenges of physical inactivity, eating habits, social contact, and more, that had arisen as a result of the pandemic and consequent home schooling. The success of this conference would not have been possible without all of our partner organizations and our sponsors. We are proud to have the patronage of the Human Rights Ombudsman of the Republic of Slovenia, Mr. Peter Svetina included among them. The positive feedback from participants confirms that the added value of on-site conferences is not only the in vivo presentations, but also the excellent opportunity to network, share best practices, and meet new people during the coffee breaks and social events. Saša Pišot and Kaja Teraž ANNALES KINESIOLOGIAE • 12 • 2021 • 2 139 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 11. MEDNARODNA ZNANSTVENA IN STROKOVNA KONFERENCA OTROK V GIBANJU Portorož, Slovenija, 4.–6. oktober 2021 V dveh letih, ki so minila od naše zadnje konference, v času restriktivnih ukrepov, ki jim je bilo včasih težko slediti, še težje pa novim pravilom prilagajati delo in spo- razumevanje, nam je uspelo, da se ponovno srečamo na 11. mednarodni znanstveni in strokovni konferenci Otrok v gibanju 2021 in uživamo gostoljubje Grand Hotela Bernardin ter obalnih mest Portorož in Piran. Tokratni delovni naslov konference Pre- magajmo posledice ukrepov omejitve gibanja je izražal, analiziral in nagovarjal teme tega časa, v znanstvenem in strokovnem jeziku. 140 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Dvodnevni program je ponudil tri plenarna in 11 uvodnih predavanj, v katerih so predavatelji predstavili aktualna dognanja, povezana s posledicami pandemije covi- da-19 na otroke. Zbornik prispevkov vsebuje 35 znanstvenih in 121 strokovnih prispevkov več kot 200 avtorjev in soavtorjev iz ducata evropskih držav. V prispevkih so predstavljene aktualne ugotovitve raziskav in primeri dobre prakse učiteljev, vzgojiteljev, pediatrov, kineziologov, dietetikov, fiziologov, psihologov, sociologov itd. pri reševanju izzivov na področju telesne (ne)aktivnosti, prehranjevalnih navad, socialnih stikov in drugega, ki so se pojavili kot posledica pandemije in šolanja na domu. Uspeh te konference ne bi bil mogoč brez vseh naših partnerskih organizacij in sponzorjev. V posebno čast pa si štejemo tudi tokratno častno pokroviteljstvo varuha človekovih pravic Republike Slovenije Petra Svetine. Pozitivni odzivi udeležencev konference potrjujejo, da dodana vrednost konferenc »v živo« niso le predavanja, temveč da so te tudi odlična priložnost za mreženje, iz- menjavo dobrih praks in spoznavanje novih ljudi med odmori za kavo in družabnimi dogodki. Saša Pišot in Kaja Teraž ANNALES KINESIOLOGIAE • 12 • 2021 • 2 141 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 WORKSHOP REPORT: PHYSICAL ACTIVITY-RELATED INJURIES PREVENTION IN ADOLESCENTS. WHAT DO WE KNOW? Piran, Slovenia, October 6, 2021 The Institute for Kinesiology Research at ZRS Koper participates in the internati- onal project Prevention of physical activity injuries in adolescents (PARIPRE), led by the University of Prešov, Slovakia. A total of eight partners, of which on the Slovenian side the Slovenian Sports Union and the National Institute of Public Health are also collaborators, are investigating risk factors and prevention programs to reduce injuries in 12-to-18-year-olds. At the workshop we presented scientific background on the importance of preventi- ve measures for different stakeholders. Altogether 79 participants from seven countries joined the workshop. The program started with opening remarks from prof. dr. Rado Pišot and prof. dr. Boštjan Šimunič from Science and Research Centre Koper, organi- zers of the workshop. This was followed by remarks from Vesna Marinko (Ministry of Health RS) who underlined the importance of the topic of physical activity-related inju- ries prevention in adolescence. Then a project presentation was given by Peter Bakalár from the University of Prešov (Slovakia). 142 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 Regular physical activity and sport is one of the most recognized determinants of health protection, particularly for the prevention of major chronic non-communicable diseases. In adolescents, physical activity and sport contribute to healthy musculo- skeletal, cardiovascular, respiratory, immune, and metabolic development and help maintain physical fitness and healthy body mass. It is also associated with several psychological and social benefits. Appropriate physical and sporting activity have no harmful effects, but there is an increased risk of injury during exercise, especially in high-intensity sports, but also in low-intensity physical activity if we are poorly prepared for it. Therefore, the prevention of physical activity and sport- related inju- ries and the identification of risk factors must be an integral part of the promotion of physical activity and sport. An increased risk of injury is also posed by the physical inactivity that is now prevalent in the modern sedentary lifestyle, which has been exacerbated during this COVID-19 era. This talk was followed with the presentation of sport injuries epidemiology by prof. dr. Jari Parkkari from UKK Institute (Finland). No less than 47% of children are injured at least once in a year, with 50% of injuries occurring in sports clubs, 30% in recreati- onal activities and 20% at school. Boys are more prone to injury than girls. Sports club membership is an underlying risk factor for hospitalization of children after injury, whi- ch must be considered as a logical cause-effect relationship. If we disregard the current situation with COVID-19 (where we can see a sharp decrease in participation in sports clubs), we have observed an increase in the number of people involved in sports clubs (in Finland from 46% in 2010 to 62% in 2016 and in Slovenia even 82% in 2019). On the other hand, the physical inactivity of children and young people (at school, at home, during leisure time) is also increasing at an extreme rate, which also affects the increase in the number of injuries during physical and sporting activity and represents a major public health problem. Afterwards, dr. Mari Leppänen from UKK Institute (Finland) presented Sport Injury Prevention Strategies and Measures and a draft of Recommendations for the prevention of physical activity-related injuries in adolescents. The latter were discussed among various stakeholders and their comments were considered and incorporated in the final version of the recommendations that was prepared following the workshop. The re- commendations were later published in a scientific journal, sent to stakeholders and are available at the webpage: https://www.paripre.eu/wp-content/uploads/2022/02/2021_ PARIPRE_Recommendations.pdf. Boštjan Šimunič ANNALES KINESIOLOGIAE • 12 • 2021 • 2 143 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 POROČILO DELAVNICE: PHYSICAL ACTIVITY-RELATED INJURIES PREVENTION IN ADOLESCENTS. WHAT DO WE KNOW? Piran, Slovenija, 6. oktober 2021 Inštitut za kineziološke raziskave ZRS Koper sodeluje v mednarodnem projektu Physical activity-related injury prevention in adolescents (PARIPRE), ki ga vodi uni- verza v Prešovu, Slovaška. Osem partnerjev, od katerih na slovenski strani sodelujeta še Športna unija Slovenije in Nacionalni inštitut za javno zdravje, proučuje dejavnike tveganja in preventivne programe zmanjševanja poškodb pri mladostnikih, starih od 12 do 18 let. Na delavnici smo predstavili znanstvena izhodišča preventivnih ukrepov za različne deležnike preventive športnih poškodb. Delavnice se je udeležilo 79 udeležencev iz sedmih držav. Po uvodnih nagovorih prof. dr. Rada Pišota in prof. dr. Boštjana Šimuni- ča iz Znanstveno-raziskovalnega središča Koper je pomembnost teme poudarila Vesna Marinko z Ministrstva za zdravje. Sledila je predstavitev projekta s strani vodje izr. prof. dr. Petra Bakalárja iz univerze v Prešovu (Slovaška). Redna gibalna/športna ak- tivnost je med najbolj prepoznanimi dejavniki varovanja zdravja, predvsem za prepre- čevanje vodilnih kroničnih nenalezljivih bolezni. V mladosti gibalna/športna aktivnost prispeva k zdravemu razvoju skeletno-mišičnega, srčno-žilnega, dihalnega, imunskega in presnovnega sistema, pomaga vzdrževati telesno pripravljenost in primerno tele- 144 REPORTS AND REVIEWS/POROČILA IN OCENE, 137–144 ANNALES KINESIOLOGIAE • 12 • 2021 • 2 sno maso. Povezana je tudi s številnimi psihološkimi in socialnimi koristmi. Ustrezna gibalna/športna aktivnost nima škodljivih učinkov, pri ukvarjanju z njo pa se pojavi povečano tveganje za poškodbe, predvsem med visoko intenzivnimi športi in tudi med nižje intenzivnimi gibalnimi aktivnostmi, če smo slabo pripravljeni nanje. Zato morata biti preprečevanje poškodb pri gibanju in športu in prepoznavanje dejavnikov tveganja sestavna dela spodbujanja gibalne/športne aktivnosti. Povečano tveganje za poškodbe pomeni tudi gibalna neaktivnost, ki je značilna za današnji prevladujoči sedentarni ži- vljenjski slog, ki se v času covida-19 še krepi. Aktualne podatke o športnih poškodbah pri mladih je predstavil prof. dr. Jari Par- kkari z inštituta UKK (Finska). Kar 47 % otrok se poškoduje vsaj enkrat v letu dni, pri čemer se 50 % poškodb zgodi v športnih klubih, 30 % med prostim časom in 20 % med šolskim časom. Dečki so poškodbam bolj podvrženi kot deklice. Članstvo v športnih klubih je temeljni dejavnik tveganja za hospitalizacijo otrok po poškodbi, kar pa je tre- ba jemati kot logično vzročno-posledično razmerje. Če odmislimo trenutne okoliščine s covidom-19 (ko beležimo velik upad vključenosti v športne klube), smo bili v zadnjih letih priča povečevanju števila vključenih v športne klube (na Finskem s 46 % v letu 2010 na 62 % v letu 2016 in v Sloveniji celo na 82 % v letu 2019), hkrati pa se izjemno povečuje tudi gibalna neaktivnost otrok in mladostnikov (v šolah, doma, v prostem času), kar tudi vpliva na povečevanje števila poškodb med gibalno/športno aktivnostjo in je velik javnozdravstveni problem. V glavnem delu je dr. Mari Leppanen z inštituta UKK predstavila osnutek strategij in priporočil Sport Injury Prevention Strategies and Measures in Recommendations for the prevention of physical activity-related injuries in adolescents. Med interaktivno delavnico smo natančno pregledali vse ukrepe priporočil in jih posodobili. Po končani delavnici smo projektni partnerji naredili čistopis priporočil, jih objavili v znanstveni reviji in z njimi seznanili vse deležnike športnih poškodb. Priporočila so na voljo na spletni strani: https://www.paripre.eu/wp-content/uploads/2022/02/2021_PARIPRE_ Recommendations.pdf. Boštjan Šimunič ANNALES KINESIOLOGIAE • 11 • 2020 • 1 145 GUIDELINES FOR AUTHORS, 145–148 GUIDELINES FOR AUTHORS 1. Aim and scope of the journal: Annales Kinesiologiae is an international interdisciplinary journal covering kinesiology and its related areas. It combines fields and topics directed towards the study and research of human movement, physical activity, exercise and sport in the context of human life style and influences of specific environments. The journal publishes original scientific articles, review articles, technical notes and reports. 2. General policy of Annales Kinesiologiae Annales Kinesiologiae pursues the multi-disciplinary aims and nature of Kinesiology with the main goal to promote high standards of scientific research. a) Reviewing: Each manuscript, meeting the technical standards and falling within the aims and scope of the journal, will be subjected to a double-blind peer-review by two reviewers. Authors can propose up to two reviewers for revision of their work and also up to two reviewers they would like to avoid. The referees are chosen by the Editors. Assessments by the referees will be presented anonymously to the author and will be returned to the author for correction. The corrected copy of the manuscript, with the list of corrections on a separate page, should be returned to the responsible Editor. b) Permissions: Authors wishing to include figures, tables, or text passages that have been published elsewhere, are required to obtain permission from the copyright owner(s) and to include evidence that such permission has been granted when submitting their manuscript. Any material received without such evidence it will be assumed that the authors hold the copyright. c) Copyright agreement: Submitting the article through the OJS (Open Journal System), the corresponding author will be asked to accept the terms of the copyright agreement. The aforementioned agreement is effective if and when the article submitted to be published in Annales Kinesiologiae is accepted. 3. Manuscript preparation a) Language and style: The language of Annales Kinesiologiae is USA English. The authors are responsible for the language, grammar, and style of the manuscript, which need to meet the criteria defined in the guidelines for authors. Manuscripts are required to follow a scientific style style. The journal will be printed in grayscale. b) The length of the manuscript should not exceed 36,000 characters (excluding spaces). Text formatting: It is required to use the automatic page numbering function to number the pages. Times New Roman font size 12 is recommended, with double spacing between lines. Use the table function, not spreadsheets, to make tables. Use an equation editor for equations. Finally, all lines need to be number, were the first line of a pages is assigned line number 1. c) Miscellaneous: Whenever possible, use the SI units (Système international d’unités). 146 GUIDELINES FOR AUTHORS, 145–148 ANNALES KINESIOLOGIAE • 11 • 2020 • 1 d) The title page should include the title of the article (no more than 85 characters, including spaces), full names of the author(s) and affiliations (institution name and address) of each author; linked to each author using superscript numbers, as well as the corresponding author’s full name, telephone, and e-mail address. e) The authors are obliged to prepare two abstracts – one short abstract in English and one (translated) in Slovene language. For foreign authors translation of the abstract into Slovene will be provided. The content of the abstract should be structured into the following sections: purpose, methods, results, and conclusions. It should only contain the information that appears in the main text, and should not contain reference to figures, tables and citations published in the main text. The abstract is limited to 250 words. f) Under the abstract a maximum of 6 appropriate Keywords shall be given in English and in Slovene. For foreign authors the translation of the key words into Slovene will be provided. g) The main text should include the following sections: Introduction, Methods, Results, Discussion, Conclusions, Acknowledgement (optional), and References. Individual parts of the text can form sub-sections. h) Each table should be submitted on a separate page in a Word document after the Reference section. Tables should be double-spaced. Each table shall have a brief caption; explanatory matter should be in the footnotes below the table. Abbreviations used in the tables must be consistent with those used in the main text and figures. Definitions of symbols should be listed in the order of appearance, determined by reading horizontally across the table and should be identified by standard symbols. All tables should be numbered consecutively Table 1, etc. The preferred location of the table in the main text should be indicated preferably in a style as follows: *** Table 1 somewhere here ***. i). Captions are required for all figures and shall appear on a separate manuscript page, under the table captions. Each figure should be saved as a separate file without captions and named as Figure 1, etc. Files should be submitted in *.tif or *.jpg format. The minimum figure dimensions should be 17x20 cm and a resolution of at least 300 dpi. Combinations of photo and line art should be saved at 600–900 dpi. Text (symbols, letters, and numbers) should be between 8 and 12 points, with consistent spacing and alignment. Font type may be Serif (Times Roman) or Sans Serif (Arial). Any extra white or black space surrounding the image should be cropped. Ensure that participant-identifying information (i.e., faces, names, or any other identifying features) should be omitted. Each figure should be saved as a separate file without captions and named as Figure 1, etc. The preferred location of the figure in the main text should be indicated preferably in a style as follows: *** Figure 1 somewhere here ***. ANNALES KINESIOLOGIAE • 11 • 2020 • 1 147 GUIDELINES FOR AUTHORS, 145–148 j) References The journal uses the Harvard reference system (Publication Manual of the American Psycho- logical Association, 6th ed., 2010), see also: https://www.apastyle.org). The list of references should only include work cited in the main text and being published or accepted for publication. Personal communications and unpublished works should only be mentioned in the text. Referen- ces should be complete and contain up to seven authors. If the author is unknown, start with the title of the work. If you are citing work that is in print but has not yet been published, state all the data and instead of the publication year write „in print“. Reference list entries should be alphabetized by the last name of the first author of each work. Titles of references written in languages other than English should be additionally translated into English and enclosed within square brackets. Full titles of journals are required (no abbreviati- ons). Where available, DOI numbers should be provided in the form of a resolvable URL https:// doi.org/10.1037/rmh0000008. Examples of reference citation in the text One author: This research spans many disciplines (Enoka, 1994) or Enoka (1994) had con- cluded... Two authors: This result was later contradicted (Greene & Roberts, 2005) or Greene and Roberts (2005) pointed out... Three to six authors: a) first citation: Šimunič, Pišot and Rittweger (2009) had found... or (Šimunič, Pišot & Rit- tweger, 2009) b) Second citation: Šimunič et al. (2009) or (Šimunič et al., 2009) Seven or more authors: Only the first author is cited: Di Prampero et al. (2008) or (Di Prampero et al., 2008). Several authors for the same statement with separation by using a semicolon: (Biolo et al., 2008; Plazar & Pišot, 2009) Examples of reference list: The style of referencing should follow the examples below: Books Latash, M. L. (2008). Neurophysiologic basis of movement. Campaign (USA): Human Ki- netic. Journal articles Marušič, U., Meeusen, R., Pišot, R., & Kavcic, V. (2014). The brain in micro- and hyper- gravity : the effects of changing gravity on the brain electrocortical activity. European journal of sport science, 14(8), 813–822. https://doi.org/10.1080/17461391.2014.908959 148 GUIDELINES FOR AUTHORS, 145–148 ANNALES KINESIOLOGIAE • 11 • 2020 • 1 Šimunič, B., Koren, K., Rittweger, J., Lazzer, S., Reggiani, C., Rejc, E., … Degens, H. (2019). Tensiomyography detects early hallmarks of bed-rest-induced atrophy before changes in muscle architecture. Journal of applied physiology, 126(4), 815–822. https://doi.org/10.1152/ japplphysiol.00880.2018 Book chapters Šimunič, B., Pišot, R., Mekjavić, I. B., Kounalakis, S. N. & Eiken, O. (2008). Orthostatic intolerance after microgravity exposures. In R. Pišot, I. B. Mekjavić, & B. Šimunič (Eds.), The effects of simulated weightlessness on the human organism (pp. 71–78). Koper: University of Primorska, Scientific and research centre of Koper, Publishing house Annales. Rossi, T., & Cassidy, T. (in press). Teachers’ knowledge and knowledgeable teachers in physical education. In C. Hardy, & M. Mawer (Eds.), Learning and teaching in physical educati- on. London (UK): Falmer Press. Conference proceeding contributions Volmut, T., Dolenc, P., Šetina, T., Pišot, R. & Šimunič, B. (2008). Objectively measures physical activity in girls and boys before and after long summer vacations. In V. Štemberger, R. Pišot, & K. Rupret (Eds.) Proceedings of 5th International Symposium A Child in Motion “The physical education related to the qualitative education” (pp. 496–501). Koper: University of Primorska, Faculty of Education Koper, Science and research centre of Koper; Ljubljana: University of Ljubljana, Faculty of Education. Škof, B., Cecić Erpić, S., Zabukovec, V., & Boben, D. (2002). Pupils‘ attitudes toward endurance sports activities. In D. Prot, & F. Prot (Eds.), Kinesiology – new perspectives, 3rd International scientific conference (pp. 137–140), Opatija: University of Zagreb, Faculty of Ki- nesiology. 4. Manuscript submission The article should be submitted via online Open Journal Systems application, which is open source journal management and publishing software at http://ojs.zrs-kp.si/index.php/AK/ about/submissions. All the communication process with authors proceeds via Open Journal System and e-mail. 5. For additional information regarding article publication, please do not hesitate to contact the secretary of Annales Kinesiologiae. ISSN 1318-0185ISSN 2232-2620 A nnaleSK inesiologiae