Short-Term Inspiratory Muscle Training and Aerobic Exercise in Women With COPD

Overview

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.

Chronic obstructive pulmonary disease (COPD) is associated with airflow limitation, respiratory symptoms, reduced exercise tolerance, dyspnea, and impaired quality of life. In women with COPD, symptom burden and dyspnea may be more pronounced even at comparable levels of airflow limitation. Inspiratory muscle dysfunction may further contribute to breathing difficulty and reduced functional capacity. Therefore, interventions targeting inspiratory muscle performance may provide clinically relevant benefits in this population. This single-center randomized controlled trial was designed to compare the effects of different short-term rehabilitation approaches in women with stable COPD. Participants were allocated to one of five parallel groups: usual care control, inspiratory muscle training, aerobic exercise, combined inspiratory muscle training plus aerobic exercise, or placebo inspiratory muscle training. The intervention period lasted four weeks, followed by a two-week detraining period during which supervised training was discontinued. The inspiratory muscle training intervention used individualized resistance based on each participant's maximal inspiratory pressure, while the aerobic exercise intervention consisted of supervised treadmill walking at submaximal intensity. The combined group received both inspiratory muscle training and aerobic exercise. The placebo inspiratory muscle training group followed a similar breathing exercise procedure but with a low resistance load. The control group continued usual medical care without supervised exercise training. The study was conducted at Hitit University Çorum Erol Olçok Training and Research Hospital. Assessments were performed before the intervention, immediately after the four-week intervention, and during follow-up on days 7 and 14 after the intervention. These follow-up measurements were included to examine whether the effects of training were maintained or reduced after the supervised intervention ended. The study focused on respiratory muscle performance, pulmonary function, walking capacity, perceived dyspnea, and psychological well-being in women with stable COPD