The influence of touchdown parameters on the performance of a high jumper

In order to maximize the mass center vertical velocity at toe-off and there by jump height the approach parameters in high jumping must be optimized. T he present study aimed to determine the influence on jump height of the app roach speed, the leg plant angle, and the knee angle at touchdown. Sixteen trials by an elite male high jumper were recorded in a single training sess ion. Direct intervention was used to induce a change in technique so that a greater range in approach speed was obtained than was observed in competit ion. The optimum approach was shown to be fast (7.0 m(.)s(-1)) with the leg planted away from the vertical (34 degrees) and with minimum knee flexion. A regression equation was obtained which was able to account for 79% of th e observed variation in jump height. Jump height performance was shown to b e most sensitive to changes in leg plant angle and knee angle at touchdown.