Maximum torque production in the quadriceps femoris muscle group using a variety of electrical stimulators

A variety of electrical stimulators were used to produce a maximum tolerable contraction (MTC) in the non-dominant quadriceps femoris muscle group of 14 normal female subjects. This was compared to each subject's maximum voluntary contraction (MVC). A robotic dynamometer (Kin-Com) was used to control and measure joint angle and isometric torque production. Results indicated considerable variation in the torque produced by each subject under the different stimulation conditions. In general there were no significant differences in the force produced by each type of stimulator. However, significant differences were observed between all MTCs and MVC. Several subjects achieved a contraction under electrical stimulation in excess of their MVC.