Effects of eccentric valuables of jump squats on jumping performance

Abstract

This study aimed to determine whether velocity of downward (eccentric:ECC) phase affect jump height, mean and peak velocity, power, force, and rate of force development (RFD) of upward (concentric:CON) phase during jump squat (JSQ) with moderate load. Fifteen university rugby players were performed JSQ conducted with ECC velocity of 2 seconds (ECC2s) and their maximum velocity (ECCMax) at 30% and 50% load of squat one repetition maximum (SQ1RM). JSQ with ECCMax showed significantly higher values of jumping height, mean and peak velocity, power, force, and RFD, in comparison with JSQ with ECC2s. These results suggest that during JSQ with a moderate load, performance of CON phase was revealed to be enhanced with faster velocity of ECC phase.