A FORMULA FOR MEASUREMENT OF LEG POWER IN THE VERTICAL JUMP

Abstract

The measurement of leg power through the execution of a standing vertical jump seems to be an on-going challenge to biomechanists. The problem is that the height of a jump is produced by the instantaneous velocity of the jumper at the moment of release from the supporting surface and neither the height of the jump nor the release velocity are measures of leg power. Thus, the challenge seems to be to develop a model through which leg power can be measured through height measures obtained from a standing vertical jump. The purpose of this paper is to present a model for the calculation of leg power based on the height of the center of mass at three positions. These positions are Y1, the lowest crouched position; Y2, the extended position just as he body releases from the floor; and Y3, the highest part of of the jump. A simple analysis based on these three heights may be used to obtain the work done in jumping, the release velocity from the floor, and an "average" vertical force exerted during the jump. From the release velocity and average vertical force, an approximate average power can be calculated.