Figure 5. The level of co-contraction of the R TA and GS muscles following a disturbance.

The level of co-contraction of the R TA and GS muscles following rapid extension of the right hip is shown for three subjects. Subject RO showed a high level of co-contraction whereas subjects JU and BZ showed a low level of co-contraction. Pearson's product moment correlation coefficients (r) for the TA and GS EMG activity are also shown