Skeletal Muscle Contraction

Abstract

Skeletal muscles produce contractile force when activated. The electrical activity of motor neurons are transmitted across the neuromuscular junction and produce muscle action potentials. The membrane depolarization of muscle fibers leads to chemical reactions which produce this contractile force. A.F. Huxley proposed the sliding filament model of muscle contraction. Huxley’s model of muscle contraction provides a biophysical basis for the generation of force, which leads to mathematical analysis based on chemical reaction rates. This model explains the static and dynamic properties of muscle. Although this is a nonlinear model it is possible to linearize it into a form convenient for use in complex macroscopic models of movement. This linearized model can use many of the tools of systems analysis developed in preceding chapters. This reduced model satisfactorily predicts muscle behavior under a variety of situations.