Experiments were performed to evaluate the leg's muscle movements during walking and running. Optical sensors were tested transversally and longitudinally adhered to the skin in the region of the gastrocnemius. Seven healthy patients were assessed at different walking and running progressive speeds. For a one step full cycle, the running speeds the period stabilized at 0,76s, whereas for walking speeds the period increased with the speed. Information was also obtained relating different patients cycles of step, which decrased as the size of the patient's leg.