Muscle activation history at different vertical jumps and its influence on vertical velocity

In the present study we investigated displacement, time, velocity and acceleration history of center of mass (COM) and electrical activity of knee extensors to estimate the dominance of the factors influencing the vertical velocity in squat jumps (SJs), countermovement jumps (CMJs) and drop jumps (DJs) performed with small (40 degrees) and large (80 degrees) range of joint motion (SROM and LROM). The maximum vertical velocity (nu 4) was 23.4% (CMJ) and 7.8% (DJ) greater when the jumps were performed with LROM compared with SROM (p