The EMG-force relationships of skeletal muscle; Dependence on contraction rate, and motor units control strategy

Abstract

The dependence of the EMG vs force relationships on skeletal muscles contraction rate, and its motor units recruitment control strategy were studied. An electrical nerve stimulation technique capable of orderly excitation of motor units according to their size with simultaneous increase in their discharge rate was applied to isometric preparations of the M. gastrocnemius muscle of the cat. Muscle force and intramuscularly recorded EMG were normalized and plotted against each other. The method of least squares (p