Influence of velocity on the human global postural strategies during the movement leading up to the vertical upside-down position

Abstract

The aim of this study was to examine the influence of the velocity on the control of the final postural equilibrium in the movement of standing up into upside-down vertical posture on the hands. Seven expert gymnasts performed the movement on a force plate of large dimensions from which the kinematic of center of mass (CoM) was studied. The first result showed that the speed of CoM was increased in the vertical axis but did not change in the antero-posterior axis. The second result showed a reduction of the duration of the anticipatory postural adjustments (APA) conversely to the speed. This was in contrast to the movements performed in the natural erect stance. These results suggest firstly that the speed of CoM corresponds to a global strategic response linked to the body's posturo-kinetic capacity, and secondly that the reduction of the APA seems to be linked to the precariousness of the final equilibrium.