USAIN BOLD – BIOMECHANICAL MODEL OF SPRINT TECHNIQUE

The aim of this research was to determine which kinematic parameters generate the maximum sprint speed of the world’s fastest sprinter, Usain Bolt. The biomechanical parameters of a double sprint step, using a 2D kinematic analysis under conditions of the realization of its maximum velocity were analyzed. The APAS computer system was used for the kinematic analysis. The data was recorded with three digital cameras CASIO EX-F1 with a frequency of 300 Hz, while the cameras were connected to one another and synchronized. The measurements were performed at the international athletics competition IAAF World Challenge in Zagreb, Croatia. Bolt reached a maximum speed of 12.42 m·s-1 in the section between 70 and 90 meters. His average stride length in this section was 2.70 m at an average frequency of 4.36 strides/s. His average contact time was 0.86 s and the average duration of his flight phase was 0.145 s. He developed a maximum vertical ground reaction force of 3956.74 N. This force corresponds to 4.1 times the weight of the athlete. The ratio between his braking and propulsion phase was 37.3% : 62.7%, which is a good indicator of an economical running technique.  The maximum speed of Usain Bolt is a combination of optimal anthropometric characteristics, motor abilities, and an extremely rational technique of sprinting gait.