Article Title



Craig Cunningham1, Sara Snow2, Mariad Cocke2, Nicole Moodie1, Derek Wassom3 & Patrick Moodie3

1Rockhurst University, Kansas City, Missouri; 2University of Kansas, Lawrence, Kansas; 3Dynamic Athletics Research Institute, Lenexa, Kansas

The majority of lower limb movement studies consist of subject pools with small population sets that make large conclusions about a specific movement. Studies are needed which incorporate larger datasets that will provide a better understanding of a specific movement pattern to make more appropriate globalized conclusions. PURPOSE: The purpose was to investigate a large dataset of vertical jumps to better understand what variables impact performance. METHODS: Using data collected from three different sites, 2,110 vertical jumps were evaluated. Data collection was performed using a marker-less motion capture system which allows for datasets to be combined. The subjects’ jump height was used to determine performance and they were placed into one of four performance zones (0-25%, 25-50%, 50-75%, 75-100%) based on the populations mean as 50%. Within these zones, 25 variables were tracked. Those groups were then statistically compared using MANOVA. RESULTS: Flexion angles during loading and joint torques produced during the concentric phase progressively increased as jump height increased. Knee loading angle and joint torques (1- Baseline, 2- +84%, 3- +115%, 4- +123%) had the largest percent change between groups. Loading and unloading time progressively decreased, rate of force development increased, ground reaction forces progressively increased at loading and unloading while force distribution between legs decreased (1- 22%, 2- 9%, 3- 6%, 4- 1%) as jump height increased. All variables listed above were significantly different (pCONCLUSION: Previous literature shows that increased loading angles yield a higher jump height, which was confirmed in this study. An underlying cause of increased jump height is not only the vertical displacement during loading, but the time elapsed during the loading phase. This decreased time also causes higher ground reaction forces. Increased GRF and rate of force development have also been shown to increase jump height, but the symmetry of the GRF and increased knee kinematics and kinetics have not been connected. With an increase in data size and tracked variables we believe this study design allows for more accurate information to be used to affect population health. Further research should be done on this movement as well as other movement types.

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