Pulmonary compliance and nonelastic resistance during treadmill exercise

Abstract

Trans-pulmonary pressure, respiratory flow, and tidal volume of seven normal subjects were measured at rest and during treadmill exercise on the level at a speed of 1.5 mph. Pulmonary compliance remained unchanged during exercise. Nonelastic resistance showed an insignificant increase (0.9—1.4 cm H2O per liter per sec). Examination of other parameters which may affect compliance were made. Functional residual capacity decreased 120—200 ml during exercise, tidal volume doubled, and respiratory frequency increased 43.5%, yet none of these factors affected the lung compliance. The phenomenon of “second wind” was experienced by four of the subjects, and nothing was observed to explain its occurrence during exercise. exercise second wind; change in functional residual capacity during exercise; effect of functional residual capacity on compliance; effect of tidal volume on compliance during exercise; effect of respiratory frequency on compliance Submitted on January 15, 1965