342 KB27 KB200520252013Sever, JernejŠarabon, Nejcštevilka:3/4letnik:61str. 105-110ISSN:0353-7455COBISSID:1536140484URN:URN:NBN:SI:doc-YHRUAP2ZslFakulteta za športŠport (Ljubljana)balanceborilne veščinemartial artsnenadna razbremenitevravnotežjestabilitystabilnostsudden releaseTaiji quanVpliv nenadne razbremenitve sile v vodoravni smeri na stabilnost pri Taijiquan|Taiji quan (TJQ) is a martial art that tries to develop the most efficient movement in battle. Its primary purpose is to try to reduce the opponent's stability and force him/her to lose balance, without losing his own balance. The purpose of this study was to compare the stability after sudden horizontal release between a group of participants who practice TJQ regularly and another group whose participants have no experience of TJQ. Each group consisted of 7 people. We used the double force plate to measure forces on the ground and a mechanism to apply the load to the participant horizontally with a trigger for sudden release of the load. The participant was loaded witha 7.5 kg weight. The direction of the force was horizontal at the height of hips. We measured the change of vertical ground reaction force (Fz), and the shift of center of pressure (COP) in anterior - posterior direction (A-P). We compared the maximum amplitude of both parameters and calculated the velocity and acceleration of movement in the direction of A-P after the sudden release of the load. The results showed that the group who practices TJQ produced a much smaller change in ground reaction force Fz than the control group. The relationship between the amplitude was 115+-49 N N vs. 182+-88 N (p = 0.002). By contrast, we didn't find significant difference between the two groups in movement of the COP, the ratio was 0.189+-0.038 m vs. 0.194+-0.051 m (p = 0.564). The load in the horizontal direction didn't directly affected the vertical force on the ground, so we can assumed that the changes of this force are consequence of reflex muscle response. The response of the TJQ group was significantly smaller, from which we can conclude, that it had better postural control and better stabilityTaiji quan (TJQ) je borilna veščina, ki poskuša razvijati čim bolj učinkovito gibanje v borbi. Njegov osnovni namen je, da poskušamo zmanjšati nasprotnikovo stabilnost in ga prisiliti k izgubi ravnotežja medtem, ko sami ravnotežja ne izgubimo. Namen raziskave je bil primerjati stabilnost pri nenadni vodoravni razbremenitvi med skupino udeležencev, ki redno vadi TJQ in sicer vadbo v dvoje in skupino, ki s tako obliko vadbe ni imela še nobenih izkušenj. V vsako skupino je bilo vključenih 7 oseb. V študiji smo uporabili dvojno ploščo za merjenje sil na podlago in mehanizem za vodoravno obremenitev s sprožilcem za nenadno razbremenitev. Merjenca smo obtežili z 7,5 kg utežjo tako, da je sila nanj delovala vodoravno v višini njegovih bokov. Merili smo spreminjanje sile navpično na podlago in premik centra pritiska v smeri naprej-nazaj, po nenadni razbremenitvi. Primerjali smo največji amplitudi obeh parametrov in izračunali hitrost in pospešek gibanja v smeri naprej-nazaj. Rezultati so pokazali, da je skupina, ki vadi TJQ, proizvedla veliko manjše spremembe sile navpično na podlago, kot kontrolna skupina. Razmerje med amplitudama je bilo 115+-49 N proti 182+-88 N (p=0,002). Nasprotno se je pri premiku centra pritiska v smeri naprejnazaj izkazalo, da med obema skupinama ni večjih razlik, razmerje je 0,189+-0,038 m proti 0,194+-0,051 (p=0,564). Z obremenitvijo v vodoravni smeri nismo neposredno vplivali na spremembo navpične sile na podlago, zato lahko predvidevamo, da so bile spremembe te sile posledica refleksnega mišičnega odziva. Skupina, ki vadi TJQ, se je odzvala z manjšimi silama v navpični smeri, iz česar lahko sklepamo, da je imela boljšo kontrolo nad držo in tudi boljšo stabilnostTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za šport