The goal of this proposal is to develop an improved mathematical model that relates mechanical output parameters (such as force and velocity) to electrical activation of the human skeletal muscle. The activation may be either in terms of the frequency of electrical stimulation or EMG. The model is to be a significant improvement over the widely used but oversimplified Hill model. The proposed work, while not breaking new ground in muscle physiology, is expected to provide a significant new aid in the analytical design of improved systems for diagnosing muscle abnormalities and for restoring muscle function through electrical stimulation.