Abstract
A viscoelastic model of the skeletal muscle consisting of contractile component and viscous and elastic components of the resting and contracting states is devised. Parameter values of all the components are determined from the physiological observations made on frog semitendinosus muscle (fiber bundle) in Ringer's solution at 10°C. Series elasticity at the contracting state increases with an increase in tension, the viscoelasticity of the resting muscle being constant. The contractile component obeys the force-load-velocity relation, so that the apparent viscous coefficient increases with exerting contractile force. Tension responses to ramp-wise stretch of the muscle are calculated on a digital computer, and a close agreement is shown between the experimental and simulated results. The model is feasible to explaining such nonlinear characteristics as the mechanical property of the contracting muscle varying with time after stimulus and with exerting force.
