The mechanical behavior of active human skeletal muscle in small oscillations.

The results of an extensive series of small-amplitude frequency-response tests of the arm flexors and extensors of ten normal adult male subjects are reported. It is concluded that a quasilinear model for muscle which had been proposed previously by one of the authors provides an adequate quantitative representation of the observed system behavior. The identified model parameters, including the stiffness and the time constants of contraction dynamics are listed for all ten subjects, thus establishing the characteristic values and ranges of variation of these parameters in normal, adult males.