THE TOUCH-DOWN AND TAKE-OFF ANGLES IN DIFFERENT PHASES OF 100 M SPRINT RUN

The variation in running velocity over a 100 m dash has been studied extensively in the last decade. Very few studies, however, have dealt with the changes in technique occurring between the second acceleration (from the normal sprinting position of run the maximal velocity until is reached), maximal velocity and deceleration phases. The purpose of this study was to quantify the touch-down (TO) and take-off (TO) angles in a 100 m sprint run, before, during and after the maximal velocity phase. Ten sprinters were filmed during these phases using a high-speed video camera operating at 250 Hz in a 100 m dash. The results of this study suggest that the Trunk Angle at TO influenced the TO angle. Furthermore, the horizontal distance between the centre of gravity and the Foot at TO, is an important technical characteristic influencing the stride length and the stride rate which provoke the running velocity variation