The effects on exercise performance of physiotherapy (PT) (8 patients) were compared with those of inspiratory muscle training (IMT) (9 patients) in severe chronic airflow limitation. Exercise performance was measured by 3 tests: the distance walked in 12 min, peak oxygen uptake on a progressive multistage exercise test, and endurance time at two thirds of maximal power output. Measurements were repeated after a 1-month control period during which no change was observed apart from an increase in the distance walked in 12 min in the PT group. The PT patients then performed graded exercise in a physiotherapy program 3 times weekly, whereas the IMT patients trained for 30 min daily, inspiring against a resistance. Measurements were repeated after 1 and 2 months of training. Physiotherapy was associated with insignificant increases in exercise performance, whereas IMT produced both an increase in endurance time and in the distance walked in 12 min. We concluded that a simple at-home training program of inspiratory muscles was more effective than this particular physiotherapy program in improving exercise performance of some patients with severe chronic airflow limitation.