Vol. 8, No 1, 2010 pp. 89 - 95
UDC 796.41.012.
Original empirical article
ONE-LEG VS TWO-LEGS VERTICAL JUMPING PERFORMANCE
Saša Bubanj1, Ratko Stanković1, Radoslav Bubanj1, Aleksandar Dimić2, Jakob Bednarik3, Edvard Kolar4
1Faculty of Sport and Physical Education, University of Niš, Serbia,
2Institute for Prevention, Treatment and Rehabilitation of Rheumatic and Cardiovascular Diseases "Niška Banja", Niška Banja, Serbia
3Faculty of Sport, University of Ljubljana, Slovenia
4Centre for University Sport, University of Ljubljana, Slovenia


Abstract. One leg vertical jump is designed to assess functional performance of lower extremity in both health and injured athletes, but there is a preoccupation in the literature to use vertical two-legs jump as measures of leg power, for the purpose of athlete assessment, performance monitoring, talent identification and in some instances prediction of readiness for training or recovery from rehabilitation. The main aim of this research was to quantify and compare the variables of manifested explosive strength, determined by different protocols of Countermovement Jump (CMJ), i.e., to determine lower extremities difference in relation to explosive strength. The sample of subjects consisted of 19 healthy, male students of the Faculty of sport and physical education from Niš, engaged in different sport activities, age 23.16±1.26 years, body height 181.37±6.51 cm and body weight 81.74±8.37 kg (Mean±Std.Dev). Subjects performed five Countermovement Jumps (CMJ), by using three different protocols of maximum vertical displacement: 1) with a left take off leg; 2) with a right take off leg; 3) with both take off legs. Wireless accelerometer «Myotest» (Sion, Switzerland), measured following variables of CMJ: Height (expressed in cm); Power (expressed in W/kg); Force (expressed in N/kg) and Velocity (expressed in cm/s). The results of descriptive statistics showed that the highest values among all variables were obtained after the CMJ protocol performed with two legs. The results of ANOVA test for repeated measurements did not show statistically significant differences between analyzed variables in CMJ with left leg protocol and CMJ with right leg protocol. However, the values obtained after the CMJ protocol with two-legs were significantly higher, in relation to both one-leg jump protocols. Derived data on the muscles' explosive strength of subjects, may help them in improving their physical abilities. Obtained results can also encourage physicians and their patients (e.g. injured athletes), to apply one-leg vertical jumping in rehabilitation process, i.e., to estimate necessary explosive strength of injured lower extremity, by assessing the healthy one and achieve the regular and balanced body look.
Key words: Explosive strength, vertical jumping, CMJ one leg-two legs protocols, difference
RAZLIKE U VERTIKALNOM SKOKU IZVEDENOM ODSKOKOM SA JEDNE I SA DVE NOGE
Vertikalni skok izveden jednom nogom se koristi u cilju procene ekplozivne snage donjih ekstremiteta i zdravih i povređenih sportista, mada se u tu svrhu u literaturi uglavnom preporučuje sunožni vertikalni skok u cilju monitoringa sportiste, tj., njegovog dostignuća, identifikacije talenata, procene spremnosti sportiste da se uključi u određeni trenažni proces i u periodu rehabilitacije. Osnovni cilj ovog istraživanja bio je da se kvantifikuju i uporede varijable ispoljene eksplozivne snage, određene primenom različitih protokola vertikalnog skoka, tzv. Countermovement Jump (CMJ), odnosno da se utvrdi razlika u eksplozivnoj snazi donjih ekstremiteta. Uzorak ispitanika se sastojao od 19 zdravih studenata Fakulteta sporta i fizičkog vaspitanja iz Niša, koji upražnjavaju različite sportske aktivnosti, muškog pola, starosti 23.16 ± 1.26 godina, telesne visine 181.37 ± 6.51 cm i telesne težine 81.74 ± 8.37 kg (Mean±Std.Dev). Ispitanici su izveli pet CMJ skokova, koristeći tri različita protokola: 1) sa levom odskočnom nogom; 2), sa desnom odskočnom nogom; 3) odskokom sa obe noge. Upotrebom bežičnog akcelerometra «Myotest» (Sion, Švajcarska), utvrđene su vrednosti sledećih varijabli CMJ: Height (visine izražene u cm), Power (snage izražene u W/kg), Force (sile izražene u N/kg) i Velocity (brzine izražene u cm/s). Rezultati deskriptivne statistike pokazali su da su najveće vrednosti svih varijabli dobijene primenom CMJ protokola odskoka sa obe noge. Rezultati ANOVA-e za ponovljena merenja, su pokazali da ne postoje statistički značajne razlike između varijabli CMJ protokola sa levom nogom i CMJ protokola sa desnom nogom. Međutim, vrednosti varijabli dobijenih CMJ protokolom sa obe noge bile su značajno veće u odnosu na oba CMJ protokola odskoka sa jednom nogom. Dobijeni podaci mogu biti od pomoći ispitanicima u poboljšanju njihove eksplozivne snage mišića. Rezultati mogu da ohrabre lekare i pacijente (povređene sportiste) da primenjuju vertikalne skokove sa jednom nogom u procesu rehabilitacije, tj., da se testiranjem i analizom rezultata zdrave noge, proceni neophodna eksplozivna snaga povređene noge, kako bi se u krajnjem dobio pravilan i uravnotežen izgled tela.
Ključne reči: Eksplozivna snaga, vertikalni skok, CMJ protokoli, razlika