Measuring Individual Muscle Force Using Ultrasound Elastography and Motion Capture

Abstract

Human musculature is over-determined so that one muscle could complete a movement that we make using several. For example, the biceps brachii is an agonist muscle for both elbow flexion and supination of the forearm. In the same way, the bicep brachii is not the only muscle activated during elbow flexion: there are other muscles that contribute to the movement. Consequently, there is not a straightforward way of knowing what muscles are contributing to a specific movement or how much force is being generated by each muscle to complete a movement. The musculoskeletal system is a load bearing system for humans. When a force is exerted on the body, it results in the body being subjected to mechanical loads, and most of the loads experienced by the joints within the body result from the internal muscle forces. Injury can occur if external loads placed on the body exceed the body’s internal tolerances, like in weightlifting and other exercises. In order to understand this relationship between external and internal forces, and how the body responds to internal loading, it is important to determine the individual force created by a muscle