Effect of expiratory muscle training on peak cough flow in children and adolescents with cystic fibrosis

Abstract

Background: Cough is an important mechanism for secretion clearance in patients with cystic fibrosis. Aim: The primary aim of this study was to investigate the effect of expiratory muscle training (EMT) on cough capacity and secondly on respiratory muscle functions and functional exercise capacity in children and adolescents with cystic fibrosis (CF). Methods: Twenty eight patients with CF were randomized as training and sham groups. Both two groups were trained with EMT protocol that involved twice/day, for at least 5 days/week during 6 weeks. In the training group, the training intensity was 30% of the maximum expiratory pressure (MEP) and according to MEP in every two weeks. In the sham group it remained at the lowest pressure (5 cmH₂O). In the assessment, “peak flow meter” for peak cough flow (PCF), “MEP and maximum inspiratory pressure (MIP) measurements” for respiratory muscle strength, “spirometry” for pulmonary functions, and “six-minute walking test” for functional exercise capacity. Results: PCF and MEP showed greater improvement in the training group compared with sham group (p=0.04, p 0.05). Conclusion: The results of the study show that EMT can use to improve peak cough flow in patients with CF.