The effect of activation level on muscle function during locomotion: are optimal lengths and velocities always used?

ABSTRACT: Skeletal muscle exhibits broad functional diversity, despite its inherent length and velocity constraints. The observed variation in morphology and physiology is assumed to have evolved to allow muscle to operate at its optimal length and velocity during locomotion. Here, we used the variation in optimum lengths and velocities that occurs with muscle activation level to experimentally test this assumption. Muscle ergometry and sonomicrometry were used to characterize force-length and power-velocity relationships, and in vivo operating lengths and velocities, at a range of activation levels. Operating lengths and velocities were mapped onto activation level specific force-length and power-velocity relationships to determine whether they tracked changing optima. Operating velocities decrease

SUBMITTER: Holt NC 

PROVIDER: S-EPMC4795037 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature