The research proposed by the PI will investigate how animals use their muscles to power their movement, both during flight and terrestrial gait. Muscle function will be analyzed in relation to the mechanical role of tendons for elastic energy savings and the design and loading of bone elements to which they attach. These studies will be carried out using state-of-the-art techniques that allow direct measurements of muscle force, muscle shortening and bone strain to be made in living animals. These in vivo measurements will allow the PI to test assumptions about muscle function, such as uniform fiber shortening, that have had to be made using more traditional indirect approaches. The research objectives will yield important basic information concerning how muscle function during animal movement relates to the strucutral organization and physiological properties of the muscle's fibers. This information will have importance for developing a better understanding of exercise-related influences on musculoskeletal function in vertebrate animals and the neuromuscular basis for controlling movement. It is also likely to yield important technological insight into applied areas, such as robotics and the design of physical therapeutic devices.
