Vol. 8, No 1, 2009 pp. 31 - 36
UDC 797.531.1
Original empirical article
THE KINEMATIC ANALYSIS OF THE GRAB AND TRACK START IN SWIMMING
Bojan Jorgić, Miloš Puletić, Ratko Stanković,
Tomislav Okičić, Saša Bubanj, Radoslav Bubanj
Faculty of Sport and Physical Education, University of Niš, Serbia
Abstract. The winner in swimming is often decided by hundredths of a second, and therefore, all the elements of the race must be practiced. The start in swimming, together with the other elements of the race, is very important for achieving better results in competitions. Nowadays, swimmers use two start techniques: the grab and track start. The aim of this study is to determine the statistically significant differences in certain kinematic parameters between the grab and track start among competitive swimmers, cadet selection. The sample consisted of 6 competitive swimmers, 15 years of age ± SD, who belong to the cadet selection of the swimming club “Argiroupoli Nautical Club“from Athens (Greece). Three swimmers performed the grab start, while the other three performed the track start. This study involved 8 kinematic parameters: flight length (FL), flight time (FT), ascending angle (AA), angle of entry (AE), velocity of the centre of mass at take-off (VCMT), velocity of head movement at takeoff (VHMT), velocity of hand movement at takeoff (VHdMT) and velocity of hip movement at takeoff (VHpMT). In order to determine the statistically significant difference between the grab and track start, we used the t-test for each kinematic parameter. According to the results obtained in this research, we can conclude that there is no statistically significant difference between the grab and track start, except in the parameter AA (p=0.04). That is why an advantage cannot be given to one of these start techniques. Instead of that, the regular and intensive drill of a chosen start technique should be applied. While doing that, the choice of a start technique must be adapted to the swimmer’s abilities and it must increase his competitive efficiency.
Key words:
the grab start, the track start, competitive swimmers, differences, kinematic parameters
KINEMATIČKA ANALIZA GRAB I TRAK STARTA U PLIVANJU
Pobednika u plivanju često odlučuje nekoliko stotinki sekunde, zbog toga se svi elementi trke moraju uvežbavati. Start u plivanju je zajedno sa ostalim elementima trke veoma važan za postizanje što boljih takmičarskih rezultata. Danas plivači uglavnom koriste dve tehnike starta: grab i trak start. Cilj ovog istraživanja bio je da se utvrde statistički značajne razlike u određenim kinematičkim parametrima između grab i trak starta, kod plivača takmičara, selekcije kadeta. Uzorak ispitanika je činilo 6 plivača takmičara, starosti 15±0.21 godina (mean±stdev), koji pripadaju selekciji kadeta plivačkog kluba “Argiroupoli Nautical Club“ iz Atine (Grčka). Trojica plivača su izvodila grab start, a ostala trojica trak start. U istraživanju je mereno 8 kinematičkih parametara: dužina leta (DL), vreme leta (TL), uzlazni ugao (UZU), upadni ugao (UPU), brzina kretanja težišta plivača pri odskoku (VTT), brzina kretanja glave pri odskoku (VG), brzina kretanja šake pri odskoku (VŠ) i brzina kretanja kuka pri odskoku (VK). Da bi se utvrdila statistički značajna razlika između grab i trak starta za svaki kinematički parametar, korišćen je t-test. Na osnovu dobijenih rezultata u ovom istraživanju zaključuje se da između grab i trak starta ne postoji statistički značajna razlika, osim u parametru UZU (p=0.04). Zbog toga se ne može dati prednost jednoj tehnici starta u odnosu na drugu. Umesto toga, najvažnije je pravilno i intezivno uvežbavanje izabrane tehnike starta. Pri tome izbor tehnike starta mora pre svega da odgovara sposobnostima plivača i povećanju njegove takmičarske efikasnosti.
Ključne reči:
grab start, trak start, plivači takmičari, razlike, kinematički parametri
