Biomechanics of Skeletal Muscle and Tendon

Skeletal muscle is the biological tissue able to transform chemical energy to mechanical energy. Skeletal muscle has three basic performance parameters that describe its function: structure and composition, force production, and movement production. From a mechanical perspective, the musculotendinous unit behaves as an elastic-contractile component (muscle fibers) in series with another elastic component (tendons) to move human body. Due to their unique hierarchical structure and composition, tendons possess characteristic biomechanical properties, including high mechanical strength and viscoelasticity, which enable them to carry and transmit mechanical loads (muscular forces) effectively. Tendons are also mechano-responsive by adaptively changing their structure and function in response to altered mechanical loading conditions. The production of movement and force is the mechanical outcome of skeletal muscle contraction. The focus of this chapter is on the biomechanical behavior of skeletal muscle and tendon as they contribute to function of the musculoskeletal system.