Kinetic Contributions of The Upper Limbs During Counter-Movement Verical Jumps With and Without Arm Swing. Issue 8 (August 2019)

• Record Type: Journal Article
• Authors: Mosier, Eric M.; Fry, Andrew C.; Lane, Michael T.
• Is Part Of: Journal of strength and conditioning research. Volume 33:Issue 8(2019)
• Publication Date: 2019-08
• Subjects: ground reaction force -- vertical jump height -- body mass -- motion capture -- center of mass; Physical education and training -- Periodicals; Weight training -- Physiological aspects -- Periodicals; Physical fitness -- Periodicals; 613.7
• DOI: 10.1519/JSC.0000000000002275
• Languages: English
• ISSNs: 1064-8011

Abstract

Abstract : Abstract: Mosier, EM, Fry, AC, and Lane, MT. Kinetic contributions of the upper limbs during countermovement. J Strength Cond Res 33(8): 2066–2073, 2019—This study examined the kinetic contributions of the upper extremities during countermovement vertical jumps (CMVJs) while using arm swing (AS) or no arm swing (NAS) conditions. Fourteen healthy men ( ± SD ; age = 24.1 ± 3.9 years) volunteered for this investigation. Subjects performed in random order a total of 6 jumps consisting of 3 AS and 3 NAS CMVJs. A motion capture system was used to analyze the kinetic data. Paired samples t -tests were used to examine the subjects' mean differences in the AS and NAS CMVJ trials ( p <0.05). Results for all subjects were determined for each jump subjects were determined for each jump performed, with statistical analyses performed on mean values for all 3 jumps per subject. The AS significantly increased the vertical jump height (VJH) by an average of 0.07 ± 0.03 m (3.0 ± 1.3 inches). Dual-energy X-ray absorptiometry scans determined that the upper limbs were 12.0% of the total body mass. Movement of the upper limbs during the AS CMVJ produced 32.2 ± 7.0% of the total mean ground reaction force (GRF), and 11.3 ± 2.2% during the NAS CMVJ. The enhancement of performance when jumping using an AS resulted in a 13.6% increase in VJH. The contribution of the upper limbs during the AS CMVJ averaged 31.5% of the peak GRF, which occurred immediately before takeoff. The upper extremities can greatly influence vertical jump performances and the accompanying kinetics. When analyzing jump GRFs, one must be aware of how much the upper limbs contribute to these forces. In addition, proper AS mechanics must be emphasized when instructing correct jump technique.