Int J Sports Med 2018; 39(09): 661-667
DOI: 10.1055/a-0633-9308
Training & Testing
© Georg Thieme Verlag KG Stuttgart · New York

The Effect of Increasing Jump Steps on Stance Leg Joint Kinetics in Bounding

Yasushi Kariyama
1   Faculty of Sport Science, Yamanashi Gakuin University, Kofu, Japan
,
Hiroaki Hobara
2   National Institute of Advanced Industrial Science and Technology, Human Informatics Research Institute, Koto-ku, Japan
,
Koji Zushi
3   Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
› Author Affiliations
Further Information

Publication History



accepted 23 April 2018

Publication Date:
20 June 2018 (online)

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Abstract

Jump distance per step in bounding exercises from the standing position increases with increasing number of steps. We examined the hypothesis that the joint kinetic variables of the stance leg would also increase accordingly. Eleven male athletes (sprinters and jumpers) performed bounding exercise, starting from the double-leg standing posture, and covered the longest distance possible by performing a series of seven forward alternating single-leg jumps. Kinematic and kinetic data were calculated using the data by a motion capture system and force platforms. Hip extension joint work were decreased at third step (1st: 1.07±0.22, 3rd: 0.45±0.15, 5th: 0.47±0.14 J•kg−1; partial η2: 0.86), and hip abduction joint power were increased (1st: 7.53±3.29, 3rd: 13.50±4.44, 5th: 21.37±9.93 W•kg−1; partial η2: 0.58); the knee extension joint power were increased until the third step (1st: 14.43±4.94, 3rd: 17.13±3.59, 5th: 14.28±2.86 W•kg−1; partial η2: 0.29), and ankle plantar flexion joint power increased (1st: 34.14±5.33, 3rd: 37.46±4.45, 5th: 40.11±5.66 W•kg−1; partial η2: 0.53). These results contrast with our hypothesis, and indicate that increasing the jump distance during bounding exercises is not necessarily accompanied by increases in joint kinetics of stance leg. Moreover, changes in joint kinetics vary at different joints and anatomical axes.