Kinesiologia Slovenica, 26, 2, 5-15 (2020), ISSN 1318-2269 Original article 5 Januša Stibilj1 Katarina Košmrlj2 Jernej Kapus3 EVALUATION OF MISTAKES IN BACKSTROKE SWIMMING OVREDNOTENJE NAPAK PRI HRBTNEM ABSTRACT Purpose. We tried to determine the perceptions of experienced swimming teachers and coaches (hereinafter "experts") regarding common mistakes in backstroke swimming. Moreover, we compared their evaluation with the evaluation of participants with no professional expertise in teaching/coaching swimming (hereinafter »non-experts«). Methods. 70 participants were recruited and divided either in the experts group (E) or in the non-experts group (NE). Group E consisted of 21 swimming coaches (11 males and 10 females; ages 34 ± 11 years) with the certificate of Slovenian Swimming association and with lengthy experience (at least 10 years) in teaching and coaching swimming. 49 undergraduate students (29 males and 20 females; ages 18 ± 1 years) without any teaching or coaching experiences in swimming were assigned to Group NE. They were asked to mark 42 mistakes that most commonly occur in backstroke swimming. They evaluated these mistakes on a seven-point scale of importance for backstroke swimming performance. Results. For 27 of 42 mistakes significant differences existed in evaluations between both groups. Group NE marked them with a significantly lower score, i.e. as less important than Group E. Conclusion. In light of the results obtained by Group E, a scale of importance of mistakes for backstroke swimming was established. This scale could be used for future swimming teachers' preparation in a way to understand the principles of backstroke with greater ease. Moreover, it could help swimming teachers and coaches classify swimmers according to their backstroke technique performance. Keywords: swimming, learning, qualitative analysis, evaluation 'Primary school Branik 2University of Primorska, Faculty of management 3University of Ljubljana, Faculty of sport Corresponding author: Assoc. prof. dr. Jernej Kapus, University of Ljubljana, Faculty of Sport Gortanova 22, 1000 Ljubljana, Slovenia Phone: ++386 1 520 77 96 Fax: ++386 1 520 77 40 E-mail: jernej.kapus@fsp.uni-lj.si IZVLEČEK Cilj. Z raziskavo smo želeli ugotoviti ocene plavalnih učiteljev in trenerjev (plavalnih strokovnjakov - E skupina) o pomembnosti najpogostejših napak pri hrbtnem. Njihove ocene smo primerjali z ocenami študentov Univerze v Ljubljani, Fakultete za šport (NE skupina), ki niso imeli znanja in izkušenj iz poučevanja plavanja. Metode. 21 plavalnih učiteljev in trenerjev (11 moških in 10 žensk; starost 34 ± 11 let z vsaj 10 letnimi delovnimi izkušnjami) ter 49 študentov (29 moških in 20 žensk; starost 18 ± 1 let) je ovrednotilo 42 napak na sedem stopenjski lestvici po pomembnosti. Rezultati. Pri 27 od 42 napak so bile ocene pri NE skupini statistično pomembno nižje od ocen pri E skupini, torej so jih vrednotili kot manj pomembne. Zaključki. Na osnovi median ocen skupine E smo izdelali lestvico napak po pomembnosti. Ta lestvica omogoča lažje razumevanje pravilne tehnike hrbtnega in je lahko v pomoč pri usposabljanju in izobraževanju bodočih plavalnih učiteljev in trenerjev. Ob tem lahko predstavlja tudi kriterij za razvrščanje plavalcev v ravni glede na njihovo znanje hrbtnega. Ključne besede: plavanje, učenje, kvalitativna analiza, ocenjevanje 6 Backstroke Swimming Mistakes Kinesiologia Slovenica, 26, 2, 5-15 (2020) INTRODUCTION The contemporary origin of technique analysis in sport lies in coaching, as there was a need for coaches to improve the performance of their athletes. Mainly, there are two different approaches for such analysis i.e. quantitative and qualitative (Lees, 2002). Quantitative technique analysis relies on biomechanical data collections methods. It is ideal for a detailed investigation of some part of sports technique, but it is less suitable for establishing characteristics of whole movement. On the contrary, the qualitative analysis of technique is carried out by observation and subjective judgement. Beside phase and temporal analysis, the "critical feature" is one of the models for the movement observation (Lees, 2002). It is defined as "the parts of phase of a movement which can be at least modified to achieve a goal" (Arend and Hinggins, 1976). Considering the goal of an appropriate athlete's demonstration of the particular movement, the diagnosis or identification of technique errors is needed knowledge for coaches (Lees, 2002). Competitive swimming is based on achieved times for a selected swim distance. Therefore, quantitative analyses are the most widely used by swim coaches. Besides measuring swim times, they are usually obtained by measuring stroke rate, stroke length, stroke index, index of coordination as well as breathing frequency. Moreover, the methods of quantitative analysis could also involve video-based techniques from which kinematics and kinetics can be derived from direct measurements of velocity and force by using various velocities and forces transducing devices (Sanders et al., 2006). However, in some cases a quantitative approach could not reflect the progress in the athlete's swimming technique. Indeed, a coach's feedback to a swimmer often relies on qualitative observation. Commonly, coaches conduct the technique analysis themselves, through observation and qualitative assessment using the naked eye and video playback (Lees, 2002; Wilson, 2008). A key advantage of this is low cost and easy to implement with large numbers of athletes (Mooney et al., 2016). Qualitative assessment is therefore based on the coach's own knowledge and experience. They have to identify the technique mistakes and remediate them. However, the first step requires an appropriate preparation and a background knowledge, such as understanding: 1.) the ideal form of a movement in each phase, and 2.) the importance of the particular mistake to technique performance. The presentations of correct form of swimming techniques are well known in written, diagrammatic as well as in pictorial form. Coaching manuals tend to rely on the sequential breaking down of a selected movement into its various phases and templates based on expert performance (Lees, 2002). In this regard, it is surprising that the research of Pion and co-workers (1988) has been, according to our knowledge, the only attempt of an evaluation of a swimming technique, i.e. breaststroke, by using mistakes assessment so far. Therefore, the purpose of this study was to determine the perceptions of experienced swim teachers and coaches regarding common mistakes in backstroke swimming. Moreover, we compared their evaluation with the evaluation of participants with no professional expertise in teaching/coaching swimming. METHODS Participants 70 participants were recruited and divided in either a group of experts (Group E) or in a group of non-experts (Group NE). Group E was comprised of 21 swimming coaches (11 males and 10 females; ages 34 ± 11 years) with the certificate of Slovenian Swimming association and with lengthy experience (at least 10 years) in teaching and coaching swimming. Group NE was comprised of 49 participants (29 males and 20 females; ages 18 ± 1 years). These non-experts Kinesiologia Slovenica, 26, 2, 5-15 (2020) Backstroke Swimming Mistakes 7 were undergraduate students without any experiences in teaching or coaching swimming. All participants had received written and oral instructions before the beginning of the study and had given their informed written consent. The institutional review board (Ethics Committee of University of Ljubljana, Faculty of Sport) approved the study protocol. The study was conducted according to the principles expressed in the Declaration of Helsinki. Procedures A self-administered questionnaire was distributed to all participants. Categories of questions included 1) teaching experiences and 2) importance of various mistakes of backstroke. The latter category was related to the assessment of a particular mistake in terms of its importance in the training program of an advanced swimmer, i.e. a potential competitive swimmer. In this way, the participants were asked to mark 42 mistakes that most commonly occur at backstroke swimming (Maglischo, 2003). Mistakes were grouped according to body position, kicking, stroking, and coordination. Before the data collection, each mistake was presented to participants by using video clips or pictures. Thereafter they evaluated them on a seven-point scale in regard of their importance for backstroke swimming performance (table 1). Table 1. Table depicting 7-point scale of importance. SCORE LEVEL OF IMPORTANCE 1 Not at all important 2 Low importance 3 Slightly important 4 Moderately important 5 Considerably important 6 Very important 7 Extremely important Statistical analyses The majority of data presented in the results are descriptive in nature. Statistical analyses were carried out by using IBM SPSS Statistics 21.0. Based on participants' evaluation, the median (Mdn) and mean score as well as the interquartile range (IQR) were calculated for each mistake. In order to investigate whether differences existed in evaluation scores between Group E and Group NE, a Mann-Whitney U test was conducted. A significance level of 0.05 was used for all analyses. Due to the median scores obtained by Group E, the scale of importance of mistakes for backstroke swimming was established. RESULTS Considering the aim of the study only the results of the E group backstroke mistakes evaluation are presented in the following figures. The mistakes are ranked from the least to the most important in all figures. The results of the NE group are presented below the figures, when they statistically differed from the results of the E group. The participants were asked to evaluate six mistakes in backstroke body position. Figure 1 displays the marking results of Group E. 8 Backstroke Swimming Mistakes_Kinesiologia Slovenica, 26, 2, 5-15 (2020) 1 - —1— 2 ■ I - 1 0 -I- Too uiucli hips Lack of body 3oclj- M,v Mi the Ir'f! atmii Failing to keep Uu Head ¡4 pushed back Holding die head