Fig. 4

Joint moments at different loads during one gait cycle in the sagittal plane. Solid lines represent means of four subjects. Shaded areas represent one standard deviation above and below the means. Each graph begins and ends at initial contact. The vertical dashed line, which represents the toe-off point for each condition, separates the stance phase (before toe off) from the swing phase (after toe off). Results are normalized by body mass (in kg). Positive angles and moments represent extension, and negative values represent flexion. BW: body weight