Figure 4:

Mechanical power generated by the A) fast leg, B) slow leg, C) fast belt, and D) slow belt throughout the stride cycle. The power generated by the treadmill belts represents the rate of mechanical work performed by each belt on the body. During the early portion of the stride cycle (~0-15%), the leading, fast leg generated a large peak negative peak in power while the trailing, slow leg generated a relatively smaller positive peak. This relationship reversed during the later portion of the stride cycle (~40-70% of the gait cycle) such that the fast leg generated a burst of positive power while the slow leg generated a smaller burst of negative power. Each trace is an average of all participants (n = 16). The stride cycle begins and ends at foot-strike of the fast limb. Blue, yellow, and red traces correspond to split-belt walking at step length asymmetries of −15%, 0%, and +15%, respectively.