Energy Levels of Human Body Segments during Level Walking

Abstract

A method is described for measuring the mechanical energy levels of the principal body segments during walking at moderate speeds on the treadmill. Together with metabolic measurements, the method provides a powerful moans of analysing human locomotion. It is shown that the energy level of the HAT (head+arms+trunk) tends to remain constant—except for a period during transition from stance to swing—and therefore acts as a semi-conservative system. The main input of muscular work occurs during the period shortly preceding and following heel contact, agreeing with electromyographic studies of muscle activity during walking. The push-pull character of walking is evident from the mechanical energy curves. The metabolic and mechanical effects of load are described, particularly as related to gravitational and inertial effects. The gross efficiency of the external work performed during walking is shown to be about 23 per cent, agreeing with figures in the literature for human muscle work.