[Exercise retraining]

Among the essential positive facts resulting from the physical training of patients with moderate to severe obstructive bronchopneumopathy, the following should be noted:-- the maximal capacity for work increases on average by 10%;-- physiologically this increment of work maximal capacity corresponds simply to a better extraction of oxygen by the muscles;--no specific central haemodynamic modification is usually observed at maximum or sub-maximum level;-- after training there is a favourable evolution of the PaO2 at rest. In the absence of spirographic modification and diffusion capacity, this increase of PO2 seems to result from an improvement of the ratio ventilation/perfusion.