Roger G. Bannister, noted one-mile runner, thrilled the world with his speed and stamina. As a physiologist he confirmed the value of oxygen inhalation during strenuous exercise, and contributed richly to our understanding of the basic mechanisms involved in physical effort.1 An interesting highlight was the observation that oxygen added to the inspired air during exercise favored the reduction in pulse rate and volume of breathing when the concentrations were 40 and 66 per cent. The studies emphasized that the capabilities in exercise are not solely the result of accelerated cardiac output but rather evidence of a more efficient diffusion of oxygen through the lung.
The physical and physiologic capabilities for strenuous exercise, developed through the process of sound body conditioning, have aroused interest in clinical medicine, especially in attempts to control the downhill course of pulmonary insufficiency. Emphysema, a striking example of physiologic failure, poses a curious paradox: