Effect of Countermovement and Arm Swing on Vertical Stiffness and Jump Performance

Abstract

Objectives To determine the effect of using arm swing and countermovement on vertical stiffness and maximum vertical jump performance.Participants A total of 25 young healthy females were participated in the study. They stood on the force plate and performed two models ofsquat jump with (SJA) and without arm swing (SJ) and two models of countermovement jump with (CMJA) and without arm swing (CMJ).Main outcome measures Vertical leg stiffness, jump height, flight time, contact time and power were compared in SJ, SJA, CMJ and CMJA.Results In the CMJs, the stiffness and jump height were significantly higher than SJA and SJ. Contact time in jumps with countermovement and/orarm swing was three times lower than SJA and SJ.Conclusion Vertical stiffness and performance parameters can be improved by using countermovement and arm swing during vertical jumpand due to enhancement in work output and ground reaction force.