The effects of electrical stimulation of normal quadriceps on strength and girth.

The effect of surging faradic electrical stimulation on the strength and girth of normal quadriceps was studied in 18 young adult females (9 experimental and 9 control). Both quadriceps of the experimental subjects received 10 treatments of 15-min duration of electrical stimulation administered over a 5-week period. Before and after the study, thigh girth was measured and knee extension strength assessed with a Cybex II, Isometrically at 65 degrees of knee flexion and isokinetically at 30 degrees/s and 60 degrees/s. There were no differences between groups in high girth. Isometric strength increased 31% in the non-dominant leg and 21% in the dominant leg (P less than 0.05). The only significant change in isokinetic strength was found in the non-dominant leg at 30 degrees/s. Surging intermittent faradic stimulation can develop both types of strength at slow speeds of motion. Such stimulation should be valuable modality for developing isometric strength when normal voluntary motion is hampered. However, it appears to have little applicability to developing the kind of strength associated with rapid movements.