Inspiratory muscle training improves breathing pattern during exercise in COPD patients

Dyspnoea is typically the main symptom limiting exercise capacity in patients with chronic obstructive pulmonary disease (COPD) [1–3]. Exertional dyspnoea has been linked to dynamic hyperinflation (DH), when lung expansion critically encroaches upon the inspiratory reserve volume (IRV) [4]. Consequently, patients develop a rapid and shallow breathing pattern, which is energetically opposite to the pattern required to minimise the work of breathing [5]. Furthermore, the restriction of tidal volume ( V T) expansion has recently been linked to daily physical activity limitation [6]. The addition of IMT to a PR programme for selected COPD patients changes breathing pattern during exercise The authors would like to acknowledge the physiotherapists V. Barbier, I. Muylaert, and I. Coosemans (Pulmonary Rehabilitation Dept, Respiratory Division, University Hospital Leuven, Belgium) for performing the pulmonary rehabilitation programme and all measurements of included patients as blinded outcome assessors. We would also like to thank Hans Scheers (Lung Toxicology and Epidemiology Research Unit, KU Leuven, Leuven, Belgium) for providing statistical advice. Regarding the access to the University Hospital Leuven rehabilitation database, we would like to thank Geert Celis (Lung function Dept, University Hospitals Gasthuisberg, Leuven, Belgium).