APPLICATION OF MAXIMUM IMPULSIVE PRINCIPLE IN THE STUDY OF THE COUNTERMOVEMENT VERTICAL JUMP

Abstract

The present study aimed to investigate the effect of the am-swing and no arm-swing on countermovement vertical jump (CMJ) and to compare the difference of male from female performing CMJ by the principle of maximum impulse to achieve movement velocity. On the other hand, we also compared the reaction characteristics of EMG signals and kinetics in order to interpret the mechanism of the am-swing during CMJ. In experiment 1, the results showed that lengthening the time of applying the force was the main factor to increase jumping height for arm-swing versus no arm-swing, and female jumpers achieved less height due to lesser strength than males. Experiment 2 indicated that the hamstrings might produce the action of plantar flexion during the am-swing of CMJ in order to postpone the gastrocnemius and soleus accelerating for contraction.