[Kinematics and kinetics of sprint acceleration].

The kinematic and dynamic characteristics of the sprint of ten (10) male athletes are presented. A Kistler force plate was used to record the following dynamic variables: force, impulse and their duration. A Photosonic, cinecamera was used to obtain the following parameters: stride length and frequency, duration of the different phases and trunk angular measures during certain phases of the running stride. This study has shown that the majority of the kinematic and kinetic factors measured are closely associated with the variation of velocity during the first 18 strides of a sprint. Moreover, two factors account for 80% of the variance in running velocity, the first one being related to the breaking phase and the second to the duration of the support phase. It was also found that the modification of sprint velocity was especially influenced by stride length and frequency. However sprint acceleration was mostly sensitive to the relative duration of the support phase.