Data from a representative subject. Rectified, low pass filtered and averaged surface EMG signals (left) solid line - mean, dashed line - standard deviation), motor modules and activation signals for overground walking (right) (A) and robot-aided walking (B) at comparable speed (2.0km/h) and body weight support (0%). Motor modules and activation signals are extracted from the concatenation of gait cycles; each grey line represents the contribution of each cycle. The analysis evidences that the impulsive structure of motor control typical of locomotion is maintained during robot-aided walking, as reflected by the activation signals (gray lines on the right). Motor modules during robot-aided walking (black histograms in the center of the figure) resulted similar to those extracted during overground walking.