Abstract

The closing volume (CV), vital capacity (VC) and CV/VC ratio were measured before and for 15 minutes following one of three exercise regimes or two hyperventilation regimes. Closing capacity (CC) and closing capacity/total lung capacity ratio (CC/TLC) were calculated. Hypercapnic and hypocapnic hyperventilation and three types of exercise ranging from moderate aerobic exercise tosevere anaerobic exercise were studied. Closing volume was measured using a helium bolus technique. There were no significant changes in CV, CV/VC, CC or CC/TLC following any of the treatments. There was a small decrease in the slow expired vital capacity following treatment. The results suggest that marked changes in ventilation prior to the measurement of closing volume do not affect the measured value. Verf.-Referat