Funds are requested for the purchase of a high-speed video system for motion analysis. This equipment would be used to study the physiology of the musculoskeletal system in vertebrates and invertebrates. Research questions to be addressed with this equipment include: (1) What factors regulate variation in motor output to skeletal muscle during normal behavior? (2) What is the effect of temperature on skeletal muscle performance? (3) How efficient are muscles, and how much work do they do during movement? Current imaging techniques for the study of musculoskeletal function (primarily conventional video and filming) do not provide adequate capabilities for the study of complex movements in three dimensions, the superposition of analog data on the movement image, or digital image manipulation and analysis.