Effects of physical training on hemodynamics and pulmonary function at rest and during exercise in patients with chronic obstructive pulmonary disease

Five patients with severe chronic obstructive pulmonary disease (COPD) underwent detailed evaluation of pulmonary function (PF), respiratory mechanics and hemodynamics before and after 18 wk of physical training (PT). PT consisted of daily progressive upright bicycle exercise. All patients demonstrated marked subjective and objective improvement in exercise tolerance. After PT exercise heart rates were significantly decreased. (p < .05). Standard PF tests were unchanged following PT. Assessment of pulmonary mechanics revealed that specific and static compliance which were increased before training decreased modestly after PT. Dynamic compliance was reduced before training and was not altered by physical conditioning. Oxygen consumption at rest and during a standardized exercise period decreased after PT (p < .05). Cardiac output, left and right heart pressures, resistances and ventricular stroke work were unchanged after PT. Systemic arteriovenous oxygen differences during exercise decreased after PT (91 ± 23 to 74 ± 21 ml/L; p < .01) secondary to a rise in mixed venous content. Increased exercise tolerance after PT in patients with COPD is probably due to increased efficiency of exercising or of respiratory muscles or both. Cardiopulmonary functions are essentially unaltered by physical conditioning.