Efficiency of muscular work: some clinical implications

The concept of mechanical efficiency is briefly reviewed. Biochemical considerations set a maximum potential efficiency of 25 percent, but, in some instances, storage of energy in elastic tissue may yield a higher apparent efficiency. Comparisons of efficiency between normal and handicapped individuals can be made in terms of the oxygen cost of specific activities, or, if due regard is paid to the effects of the primary disease, the simpler indexes of pulse rate and ventilation may be used. Measurements of efficiency can be helpful in improving the working technique of both the healthy individual and the handicapped person, Useful gains of efficiency can result only if tasks initially have an efficiency substantially below the theoretical ultimate of 25 percent.