Frequency distributions for pulmonary function, peak V′o₂, BDI score and physical activity.

<p>a) forced expiratory volume in 1 second (FEV₁); b) FEV₁/forced vital capacity (FVC) ratio; c) total lung capacity (TLC); d) functional residual capacity (FRC); e) residual volume (RV); f) diffusion capacity (<i>D</i>lco); g) peak oxygen uptake (V′o₂ peak); h) baseline dyspnea index (BDI) score; i) number of steps per day; j) and daily time spent in physical activity >3 metabolic equivalents (METs). GOLD: Global Initiative for Chronic Obstructive Lung Disease.