A Combined Inspiratory and Expiratory Muscle Training Program Improves Respiratory Muscle Strength and Fatigue in Multiple Sclerosis

Abstract Objective To determine the effects of a short-duration, combined (inspiratory and expiratory), progressive resistance respiratory muscle training (RMT) protocol on respiratory muscle strength, fatigue, health-related quality of life, and functional performance in individuals with mild-to-moderate multiple sclerosis (MS). Design Quasi-experimental before-after trial. Setting University rehabilitation research laboratory. Participants Volunteers with MS (N=21) were divided into 2 groups: RMT (n=11; 9 women, 2 men; mean age ± SD, 50.9±5.7y, mean Expanded Disability Status Scale score ± SD, 3.2±1.9) and a control group that did not train (n=10; 7 women, 3 men; mean age ± SD, 56.2±8.8y, mean Expanded Disability Status Scale score ± SD, 4.4±2.1). Expanded Disability Status Scale scores ranged from 1 to ≤6.5. No patients withdrew from the study. Intervention Training was a 5-week combined progressive resistance RMT program, 3d/wk, 30 minutes per session. Main Outcome Measures The primary outcome measures were maximal inspiratory pressure and expiratory pressure and the Modified Fatigue Impact Scale. All subjects completed secondary measures of pulmonary function, the six-minute walk test, the timed stair climb, the Multiple Sclerosis Self-Efficacy Scale, the Medical Outcomes Study 36-Item Short-Form Health Survey, and the Physical Activity Disability Scale. Results Maximal inspiratory pressure and expiratory pressure (mean ± SD) increased 35%±22% ( P