DYNAMIC CONTRIBUTION ANALYSIS ON THE PROPULSION MECHANISM OF SPRINTER DURING INITIAL ACCELERATION PHASE

Abstract

The purpose of this study was to propose a method that quantifies the functional roles of the support leg joint torques during sprinting acceleration phase. The acceleration of whole-body centre of gravity caused by the joint torques at 1st, 3rd, 5th and 7th steps from the crouch start were calculated based on the equation of motion for the whole body modeled as a linked system of fifteen rigid segments. The generation mechanism of eccentric ankle joint torque was quantified as the contributions of joints torques to the generations of joint angular velocities. The results indicate that 1) the eccentric plantarflexion torque is the largest contributor to the whole-body propulsion, 2) the eccentric plantarflexion torque is generated by the torques of hip and knee joints, and 3) the step number influences the propulsion mechanism.