Figure 1. Maximal amplitude of centre of pressure (CoP) displacement in antero-posterior direction during upright stance.

The A-P_max for young (open bars) and elderly adults (filled bars) with eyes open on a rigid surface (REO) and a foam mat (FEO) and with eyes closed on a rigid surface (REC) and a soft mat (FEC). The displacements are greater for elderly adults than for young adults (age main effect, P < 0.05). † Significant differences between supports, P < 0.05. ‡ Significant differences between vision conditions, P < 0.05.