This study was designed to apply the stimulation system developed in our laboratory to investigate how the stimulation conditions affect the muscle contractile characteristics in the isometric condition as well as during the FES standing/walking. Four paraplegic and ten healthy subjects participated in this study, and their knee extensors were voluntary contracted or electrically stimulated to measure the muscle force and the fatigue index for different waveforms of the pulse train. We also investigated different combinations of the electrode positions during standing/walking. It was confirmed that continuous and high-frequency stimulation causes faster fatigue than intermittent and low-frequency stimulation. Fatigue resistance was higher around the optimal muscle length than at a stretched position in healthy subjects, whereas the opposite was observed in paralyzed subjects. The paired t-test results with the level of significance at 0.01 indicated that the sinusoidal waveform generated the largest torque among the four typical waveforms. Although statistically not very significant, the sinusoidal waveform also generated, in general, the highest fatigue resistance at an intensity level below the supramaximal stimulation. One of the paraplegic subject who participated in the standing/walking program can now stand up for 1 minute and 50 seconds with the knee extensors, and walk for about 5 minutes at the speed of 12m/sec.