Fig. 6

Measurements of the force produced by the vastus lateralis muscle in subject P5 during Experiment 2, under two conditions: a) moderate electrical stimulation intensity (60 mA) and b) high electrical stimulation intensity (100 mA). Forces produced by the vastus lateralis under SDSS and SES electrode configurations are represented by red and blue lines, respectively. Horizontal black lines indicate the time to fatigue (TTF), and the shaded areas under the force-time curves represent the force-time integral (FTI)