The relationship between physical and physiological variables and volleyball spiking velocity

Thirteen female NCAA Division I volleyball players were given a battery of tests to assess various physical and physiological variables. Tested were body fat %, peak upper body power, arm segment lengths, vertical jump, and peak isokinetic torque of four arm motions—arm extension at the shoulder joint, arm internal rotation at the shoulder joint, forearm extension at the elbow joint, and hand flexion at the wrist joint—at three velocities (90,180, and 270°/sec). The subjects were also assessed for maximum spiking speed (SSM) by use of a radar gun (18.1 ± 1.77 m s^-1). At the p < 0.05 level only two variables were found to be significantly correlated to SSM: Arm extension torque at 270°/sec (AE270) (r = 0.64) and standing reach (SR) (r = -0.58). These results suggest that for collegiate female volleyball players, shoulder extension strength at high speed is the dominant alterable physiological variable related to spiking speed.