Sarcomere length operating range of vertebrate muscles during movement.

The force generated by skeletal muscle varies with sarcomere length and velocity. An understanding of the sarcomere length changes that occur during movement provides insights into the physiological importance of this relationship and may provide insights into the design of certain muscle/joint combinations. The purpose of this review is to summarize and analyze the available literature regarding published sarcomere length operating ranges reported for various species. Our secondary purpose is to apply analytical techniques to determine whether generalizations can be made regarding the "normal" sarcomere length operating range of skeletal muscle. The analysis suggests that many muscles operate over a narrow range of sarcomere lengths, covering 94+/-13 % of optimal sarcomere length. Sarcomere length measurements are found to be systematically influenced by the rigor state and methods used to make these measurements.