Effect of exercise on pulmonary diffusing capacity

Abstract

The effect of graded exercise on the pulmonary diffusing capacity for both oxygen and carbon monoxide measured simultaneously was studied in healthy young adults by steady-state methods. Pulmonary diffusing capacity for oxygen increases progressively with increasing severity of exercise; it exceeds the Dl_CO at high levels of exercise by amounts greater than can be accounted for by the difference in diffusivity of the test gases. Diffusing capacity for carbon monoxide increases less than Dl_OO2 for comparable grades of exercise but no definite plateau value could be established. The supine or upright body position does not influence the values of either Dl_OO2 or Dl_CO during exercise. Diffusing capacity of the lung for oxygen does not limit the maximum levels of exercise which may be achieved by normal man. Submitted on August 6, 1962