Advantage of center of pressure feedback on static element performance for gymnasts and coaches
Résumé
Visual center of pressure (COP) feedback (FB) has a positive effect in young adults [1]. These results concern dynamic parameters; however, in gymnastics only kinematics was judged. The purpose of this study was to know if CoP FB improves gymnast postural control and if CoP explains movement performance. One gymnast performed a static element on one leg during 20 s with and without CoP FB on platform and on mat. These four conditions were repeated three times while a motion analysis system synchronised with a force platform collected kinematics and dynamics data. Joint moments of the support leg, CoP confidence ellipse and distal segments range of motion were calculated. Ellipse area was larger with CoP FB. On mat condition, CoP was more in front of foot than on platform condition. In platform with CoP FB condition, gymnast placed his CoP on the geometrical foot center. Only on mat, joint moments varied significantly. FB encouraged gymnast to place CoP in the middle of his foot. This strategy is mechanically efficient but gymnast was not muscularly in the habit of balancing in this configuration. FB doesn't improve performance but could be usefull for skill learning. In gymnastics CoP did not explain balance quality because of kinematical constraints; therefore it did not help gymnasts and coaches to judge the performance.