Estimation of the distribution of intramuscular current during electrical stimulation of the quadriceps muscle.

Electrical stimulation is commonly used for strengthening muscle but little evidence exists as to the optimal electrode size, waveform, or frequency to apply. Three male and three female subjects (22-40 years old) were examined during electrical stimulation of the quadriceps muscle. Two self adhesive electrode sizes were examined, 2 cm x 2 cm and 2 cm x 4 cm.