A force-torque analysis of the kip on the horizontal bar

The purpose of this study was to determine the forces and torques on the horizontal bar during the kip. Six Canadian male gymnasts were filmed using a high speed camera during a short gymnastic routine including a kip on a horizontal bar which was wired with strain and torque gauges. During the performance, voltage outputs representing force and torque were amplified and recorded on tape. The force-torque data were then subjected to computer analysis. Maximum forces and torques were determined and force-angle plots were normalized by dividing force by body weight. The range of maximum forces was 1344-1563 N with a mean of 1444 N, which was approximately 2.3 times the body weight. The maximum forces were obtained when the center of mass was almost directly below the bar with the timing of maximum force application ranging +/- 0.1 sec from either side of 180 degrees. Maximum torques ranged from 10.0-21.0 N X m (Mean 17.3 N X m).