Flow-volume Curves and Breathing Patterns during Exercise in Patients with Obstructive Lung Disease

Abstract

Flow-volume curves were recorded in 12 patients with chronic obstructive lung disease at rest, and during forced expiratory vital capacity (MEFV curves) and work. At rest most patients breathed along the MEFV curves, and all reached it at light exercise. During maximal exercise somewhat higher flows were achieved than at corresponding lung volume in the MEFV curve. Respiratory mid-position was increased. Gas exchange studies during exercise did not explain the limitation of exercise tolerance.