20 patients suffering from chronic obstructive lung disease (COLD) were submitted to a 6-month rehabilitation program including breathing exercises only (A) or coupled with bicycle training (B). Functional results obtained at rest were the following: For A: Nonsignificant changes in FRC, RV, FEV1 Raw, Pa O2, pH, Pp, VO2 max SL but significant changes (p < 0.05) for TLC (+214 cm3), VC (+171 cm3), DLCO (+1.79 ml), Pa CO2 (-2.9 mm Hg). For B: Similar changes as for A with additional significant changes in PaO2 (+7.4 mm Hg) VO2 max SL (+250 ml) and Pp (-4 mm Hg). These results, although minimal, are attributed to improved respiratory muscle strength and improved alveolar ventilation. Exercise training adds an increased ability to sustain higher loads. © 1979 S. Karger AG, Basel.