Can a rheological muscle model predict force depression/enhancement?

J Biomech. 1998 Dec;31(12):1093-9. doi: 10.1016/s0021-9290(98)00132-8.


A new phenomenological model of activated muscle is presented. The model is based on a combination of a contractile element, an elastic element that engages upon activation, a linear dashpot and a linear spring. Analytical solutions for a few selected experiments are provided. This model is able to reproduce the response of cat soleus muscle to ramp shortening and stretching and, unlike standard Hill-type models, computations are stable on the descending limb of the force-length relation and force enhancement (depression) following stretching (shortening) is predicted correctly. In its linear version, the model is consistent with a linear force-velocity law, which in this model is a consequence rather than a fundamental characteristic of the material. Results show that the mechanical response of activated muscle can be mimicked by a viscoelastic system. Conceptual differences between this model and standard Hill-type models are analyzed and the advantages of the present model are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Animals
  • Cats
  • Elasticity
  • Forecasting
  • Isometric Contraction / physiology*
  • Linear Models
  • Models, Biological*
  • Muscle Fibers, Skeletal / physiology
  • Muscle Fibers, Skeletal / ultrastructure
  • Muscle Relaxation / physiology
  • Muscle, Skeletal / anatomy & histology
  • Muscle, Skeletal / physiology*
  • Rheology
  • Stress, Mechanical
  • Time Factors
  • Viscosity