Effect of physical training on head-hip co-ordinated movements during unperturbed stance

A cross-correlation analysis between head and hip lateral accelerations has been used to analyse the effects of sport training (in experts in judo or classical dance as compared to controls) on postural strategies during unperturbed stance. Subjects were standing in the sharpened Romberg position on either a hard or foam rubber support. The main results were: (1) several non-visual and ankle-like strategies (head-hip movements in the same sense) were used by both groups on both supports; (2) two types of lateral hip strategies (head-hip movements in opposite sense) were seen in controls on soft support only, and were mainly modulated by vision. Training appears to result in a shift from a visual to a proprioceptive dominance in the regulation of postural control in unperturbed stance.