Passive transverse mechanical properties of skeletal muscle under in-vivo compression

The objective of the present study is to determine the passive transverse mechanical properties of skeletal muscle. Compressionexperiments were performed on four rat tibialis anterior muscles. To assess the stress- and strain-distributions in the muscle duringthe experiment, a plane stress model of the cross section was developed for each muscle. The incompressible viscoelastic Ogdenmodel was used to describe the passive muscle behaviour. The four material parameters were determined by fitting calculatedindentation forces on measured indentation forces. The elastic parameters, mu and alpha were 15.6 kPa and 21.4 kPa respectively.The viscoelastic parameters, delta and t, were 0:549 and 6:01 s. When applying the estimated material parameters in athree-dimensional finite element model, the measured behaviour can be! accurately simulated.