Static block jump techniques in volleyball: upright versus squat starting positions.

The difference in maximal jump height between static block jump starting from an upright position (upright BJ) and static block jump starting from a squat position (squat BJ) was determined in 10 division II collegiate women volleyball players. Also determined was the difference in take off time for quick block jump, to a constant point above the net, between upright BJs and squat BJs. An AMTI force plate and a video camera (60 Hz) were used to collect the data. Each subject performed three maximal upright BJs and three maximal squat BJs, and five quick upright BJs and five quick squat BJs, randomly. The highest jump for maximal upright BJs and squat BJs, and the fastest jump for quick upright BJs and squat BJs were recorded. There was a significant difference (p < 0.03) between maximal upright BJs and squat BJs in height jump; maximal upright BJ (33.2 cm) was higher by 1.2 cm. No significant difference (p > 0.5) was found for the fastest take off time (approximately 0.7 s) between quick upright BJs and squat BJs. These results suggest that college women volleyball players can jump higher from the upright, compared with the squat, position. They can take off to the same block position equally quickly from either the upright or squat starting position. These data may suggest that conditioning coaches should identify their players' preferred BJ position and incorporate a specific training program to enhance the players' power. Furthermore, the coaches may need to incorporate more specific squat endurance exercises.