Fig. 7

Normalized RMS values of the EMG during progressive efforts in the eight directions with the corresponding LL joint moment directions and predominant muscular activity. Standard deviations are indicated by a bar. Four muscle synergies were previously identified during gait: synergy 1 includes activity of the VM, RF and GM (red); synergy 2 includes activity of MG and SO (orange); synergy 3 includes activity of TA and RF (blue) and synergy 4 includes activity of LH and MH (grey)