The sliding filament model of muscle contraction. III. Stability analysis and sinusoidal perturbations

A theoretical model of the energy transducing part of a single sarcomere, which has previously accounted for most of the steady state energetic and dynamical properties of striated muscle, is subjected to stability analysis. The steady states of isotonic and isometric contraction turn out to be stable and the magnitudes of the characteristic roots allow accurate reduction of the original seven state theory to a four state theory. Both versions possess a complex pair of roots giving a damped oscillatory character to the contraction velocity, the tension generated and the populations of the crossbridge states.