CONTRIBUTIONS TO BRAKING IMPULSE DURING INITIAL ACCELERATION, TRANSITION AND MAXIMAL VELOCITY IN SPRINTING

The aim of this study was to quantify the magnitude of braking impulse induced on the centre of mass by the accelerations at the foot-floor joint during steps three, nine and 19 of maximal sprinting. An induced acceleration analysis was performed to quantify the induced centre of mass accelerations. The accelerations at the foot-floor joint following touchdown generated -0.02 ± 0.01 m.s-1 (143 ± 72%), -0.04 ± 0.01 m.s-1 (80 ± 47%) and - 0.07 ± 0.01 m.s-1 (50 ± 13%) of the total relative braking impulse during steps three, nine and 19. A large portion of these foot-floor accelerations resulted from the deceleration of the foot at touchdown. The results suggest that minimising horizontal foot velocities prior to touchdown will result in reduced braking forces. Further research is required to empirically investigate this mechanism in an applied setting