The purpose of this study was to clarify the differences of the motions during the preparation for takeoff and the contact takeoff between the foul jumps and the cleared jumps in the long jump, and to get hints for coaching to prevent the foul jumps. The subjects were five male student long jumpers. Their motions during the phase of preparation for takeoff and the contact takeoff were videotaped by high speed VTR cameras. The analyzed jumps were the longest distance of the foul jumps (7.15±0.39m) and the longest distance jump of the cleared jumps (7.12±0.41m). The results were summarized as follows:
1. In the second-last stride of the foul jumps, the height of the center of gravity was higher than that of the cleared jumps, and the recovery motion of the lead leg was delayed than that of the cleared jumps.
2. In the last stride of the foul jumps, the footfall position was closer to takeoff line than that of the cleared jumps.
3. In the contact of the takeoff of the foul jumps, the swing downward of the takeoff leg and the swing to body of the lead leg were delayed than that of the cleared jumps. And the foot joint of the takeoff leg was more extended than that of the cleared jumps.
Consequently, it was inferred that the footfall position of the last stride and the foot joint angle in the contact of the takeoff were important characteristics on the foul jumps.
