The Relationship between selected kinematics variables of the take-off phase and volleyball jump top spin and jump floating serves
Paper ID : 1089-12THCONG
1Phd student,Sport Biomechanics,Faculty of Physical Education & Sport Sciences,University of Kharazmi,Tehran,Iran
2Full Professor,Sport Biomechanics,Faculty of Physical Education & Sport Sciences and Kinesiology Research Center,Kharazmi University,Tehran,Iran
Volleyball serve is one of the most important components for attacking in sport competitions. The aim of this study was to determine the relationship between kinematic selected variables in take-off phase of jump serve and float serve. Sixty six jump serves (30 serves) and float serves (36 serves) were performed by twenty two elite volleyball players (10 for jump serve and 12 for float serve). Two-dimensional recording of the performances was done and favorable kinematic variables were calculated. Among descriptive statistics components, average and standard deviation were selected for describing the data, and Shapiro-Wilk test was used for normality testing of data, and among inferential statistics tools, correlation was used for determining the relationship of selected biomechanical variables and performance with p≤0.05 as the threshold level of significance. The results of the study indicated the significant relationship between center of mass velocity and acceleration, horizontal and vertical movement of center of mass, ankle angle in TD, MKF, and TO times, knee angle in TD, MKF, TO times, hip angle in TD, MKF, TO times, horizontal and vertical velocity in take-off, and take-off resultant velocity, all with jump height in float serve, while here was no significant relationship between time and angle of take-off, take-off vertical velocity, all with jump height in float serve and among aforementioned variables with success of volleyball players in float serve. with respect to the findings of the study indicating the relationship of selected kinematic variables in take-off phase with jump height in both jump serve and float serve, a focus on the exercise to improve the jump performance of players in order to a better performance of jump serve and float serve is recommended.