Laboratory assessment of muscular strength is often used as the criterion of whole muscle function in physiological testing. The accuracy and reliability of these measurements greatly depends upon the isolation of the muscle or muscle groups being tested. For this reason the knee extensor muscles have predominantly been chosen to evaluate various physiological adaptations to exercise. However, there are various physiological models where it would be advantageous to assess the strength characteristics of the calf muscle group.

Recently we have made various attempts to measure the strength and fatigability characteristics of the calf muscles. Using previous instrumentation/techniques to interface human subjects to assess muscle performance, we have been unable to adequately restrain and measure the forces generated by the triceps surae. To overcome these difficulties, we have developed a restraint device incorporating an isokinetic dynamometer. The purpose of this article is to describe the device and present some basic strength and fatigability measurements of the calf muscles along with day to day variation and reliability results.