Fig. 5

Co-contraction index (CI) between both age groups during functional stability boundary in each condition. The measures were also divided into two phases (acceleration, deceleration). Significant differences (p < 0.017) between ages (young, elderly) are indicated by *. Significant differences (p < 0.017) between conditions (preferred, fast) are indicated by †. Significant differences (p < 0.017) between phases (acceleration, deceleration) are indicated by #.