Brief Summary:
This randomized controlled trial evaluated the short-term effects of inspiratory muscle training, aerobic exercise, combined inspiratory muscle training and aerobic exercise, placebo inspiratory muscle training, and usual care in women with stable chronic obstructive pulmonary disease (COPD). The study aimed to determine whether these interventions improve respiratory muscle strength, pulmonary function, walking capacity, dyspnea, and psychological well-being after a four-week intervention period. A secondary aim was to examine whether any improvements were maintained during a two-week detraining period after supervised training was stopped.
Participants were randomly assigned to one of five groups: control, inspiratory muscle training, aerobic exercise, combined inspiratory muscle training and aerobic exercise, or placebo inspiratory muscle training. Outcomes were assessed at baseline, after the four-week intervention, and on days 7 and 14 after the intervention. The main outcome was the change in maximal inspiratory pressure. Secondary outcomes included maximal expiratory pressure, peak inspiratory flow rate, inspiratory volume, forced vital capacity, forced expiratory volume in one second, six-minute walk distance, dyspnea, and well-being.
The study hypothesis was that inspiratory muscle training, either alone or combined with aerobic exercise, would improve respiratory muscle function, functional capacity, dyspnea, and well-being in women with COPD, and that the magnitude and persistence of these effects would differ between intervention groups.