Effect of addition of exercise to chest physiotherapy on sputum expectoration and lung function in adults with cystic fibrosis

Promotion of sputum expectoration by chest physiotherapy is an essential part of cystic fibrosis management. The role of exercise in improving sputum expectoration and lung function in these patients is more contentious. We therefore investigated the effect of adding an exercise programme to conventional chest physiotherapy in eight adult subjects (four male) with cystic fibrosis. Subjects were treated on two non-consecutive days of the second week of a course of in-patient antibiotic therapy in a cross-over fashion. On the exercise and physiotherapy day, subjects exercised 60 min before physiotherapy. On the physiotherapy alone day, subjects rested for 60 min instead of exercising. Physiotherapy was administered on both study days (postural drainage, percussion, deep breathing, vibrations, forced expiratory technique and coughing). Lung function tests were performed at baseline, after exercise or rest and again immediately and 30 min after physiotherapy. Sputum weights were measured in the 60 min of exercise or rest (period A) and for the 60 min physiotherapy period and 30 min after physiotherapy (period B). Mean total sputum expectoration (period A and B) was 14 g on physiotherapy alone and 21·5 g (4·8) on exercise and physiotherapy (mean difference 7·5 g, 95% CI 1·4–13·6 g, P=0·02). Mean sputum weights during period A (i.e. rest vs. exercise) on physiotherapy alone and exercise and physiotherapy were 2·6 and 7 g respectively (mean difference 4·4 g, 95% CI −0·07–8·8 g, P=0·053). Values for mean sputum weights during physiotherapy (period B) on physiotherapy alone and physiotherapy plus exercise were 11·4 and 14·5 g respectively (mean difference 3·1 g 95% CI 1·2–5·1 g P=0·007). No significant difference in FEV1, FVC, FEF25–75 and peak expiratory flow rate was shown between physiotherapy alone and physiotherapy and exercise. In conclusion, exercise itself leads to more sputum expectoration than occurs at rest and further increases sputum clearance afforded by physiotherapy. However, neither physiotherapy nor exercise have significant effects on lung function acutely.