FIG. 4.

Two weeks postoperative EMG activity and generated force from the left leg muscles during attempts to perform left knee flexion in conditions of no stimulation (left) or 3.5 mA stimulation (right). The lowest row depicts the associated knee flexion force (in N) over a 2-second period. The MH is active, and knee flexion occurs both with and without stimulation. There is greater intensity, TA coactivation, and force generation with stimulation. The SOL and RF show millisecond-long bursts of activity that are more frequent during stimulation. Note that the magnitude of intensity is approximately 1 order of magnitude larger than in the previous week.