The Effect of Load on Muscle Output 1

Abstract

Analytic consideration of muscle output resulted in an expression that relates the power output of a muscle to the imposed load. The simplest theory predicted that maximum power output would occur when the load impedance was equal to the impedance of the muscle system involved. Modification of this theory to accommodate the inverse type of relationship between the force generated and the speed of contraction, in agreement with physiological considerations, predicted the maximum power output at a load impedance (moment of inertia) five to ten times the impedance of the muscle system involved. Experimental observations over a wide range of loads on a specially constructed inertial dynamometer confirmed the predictions and gave a power curve similar to the predicted one.