Complementary inspiratory muscle training during pulmonary rehabilitation in COPD patients with inspiratory muscle weakness – A subgroup analysis of a randomized, controlled trial (IMTCO study)

Abstract

Background: Inspiratory muscle dysfunction occurs in patients with chronic obstructive pulmonary disease (COPD) and is associated with dyspnea and decreased exercise capacity. Aim of this study was to investigate additional benefits of adding inspiratory muscle training (IMT) to a general exercise training program during pulmonary rehabilitation (PR) in COPD patients with inspiratory muscle weakness. Methods: 70 COPD patients (FEV1: 39±13%pred., PImax: 51±14 cmH2O) participated in this randomized controlled trial. All patients performed a 3-week comprehensive inpatient PR including standardized endurance and strength training. On top, patients performed supervised IMT on 7 days/wk randomized into an intervention group and a Sham-IMT group (initial IMT pressure: 61±15% of PImax and 13±8% of PImax, respectively) Results: At 3 weeks, PImax improved significantly more in the IMT group (IMT: 18±12cmH2O vs. 6±11cmH2O, p Conclusion: A complementary inspiratory muscle training on top of a general exercise training program in COPD patients with inspiratory muscle weakness significantly improved inspiratory muscle function. However, these benefits did not transfer into further improvements of functional exercise capacity.