Determination of Optimal Relevant Joint Angles for Vertical Jump Height Across Teenagers with Differing Amounts of Jumping Experience

Reaching one’s maximum jump height requires optimizing one’s jump techniques. In order to find this optimal jump technique, three high school participants with varying vertical jump (VJ) abilities recorded videos of themselves with varying degrees of maximum/minimum shoulder, knee, and hip angles—with or without respect to the horizontal—at the isometric phase of a regular countermovement (CM) VJ or countermovement jump (CMJ). We hypothesized that VJ height would increase as each joint’s angular displacement increases from its initial position. We generated six graphs—two graphs per joint and each graph with three separate lines—using the VJ height measurements with the respective independent variables to determine the optimal relevant joint angles for maximum VJ height. Results showed that the shoulder angle without respect to the horizontal (SA), knee angle with respect to the horizontal (KAH), and the hip angle with respect to the horizontal (HAH) possessed a more consistent correlation with VJ height across the subjects compared to the same respective angles with opposite relations to the horizontal. We found that the optimal respective joint angle differs across subjects with varying levels of sport and VJ experience: participants with greater relative experience showed a better capability to absorb CM force exerted from greater limb displacement from its initial position.