ABSTRACT
The hydrolysis of A TP is the primary source of chemical energy for skeletal muscle metabolism, and the rate of hydrolysis varies depending on the intensity of the muscle contraction. Thermodynamic questions thus arise concerning the relationship of energy utilization to mechanical work and to heat production. Insofar as the respiratory muscles behave as other skeletal muscles, some general principles can be inferred; however, the particular requirements of the respiratory muscles warn against the glib assumption that they are the same as all other skeletal muscles. The general problems of muscle energetics are dealt with in several excellent reviews and original works (l-9).
