Inspiratory muscular training in chronic stroke survivors: a randomized controlled trial. Respiratory muscle training improves cardiopulmonary function and exercise tolerance in subjects with subacute stroke: a randomized controlled trial.
To assess the effectiveness of inspiratory muscular training (IMT) on measures of strength, resistance, functional performance, and quality of life (QOL) for chronic stroke survivors.
                Double-blinded randomized controlled trial.
                Research laboratory.
                Subjects (N=21) with stroke (11 men, 10 women; maximal inspiratory pressure [MIP] <90% of predicted values) were randomly assigned to the experimental (n=11) and control groups (n=10); 18 participants completed all testing and training.
                Interventions were based on home-based training, with resistance adjusted biweekly to 30% of MIP for the experimental group. The control group underwent the same protocol without the threshold resistance valve. Both groups received home training 30 minutes a day 5 times a week for 8 weeks.
                MIP, inspiratory muscular endurance (IME), functional performance, and QOL.
                There were significant between-group differences for the MIP and IME measures. Significant changes were observed for only the experimental group for MIP (67.8±14.6 at baseline to 102.2±26.0cmH(2)O at posttraining) and IME (31.8±19.3 to 49.2±21.1cmH(2)O). No statistically significant differences were observed for measures of functional performance and QOL.
                Significant short-term effects of the IMT program for inspiratory strength and endurance were observed in chronic stroke survivors. These findings gave some indications that IMT may benefit people with stroke, and it is feasible to be included in rehabilitation interventions with this population.
                Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved. To determine whether two types of exercise--breathing retraining (BRT) and inspiratory muscle training (IMT)--improve on cardiopulmonary functions and exercise tolerance in patients with stroke.
                A randomized controlled trial.
                Education and research hospital.
                Forty-five inpatients with stroke (24 men, 21 women) were recruited for the study. The subjects were randomized into three groups: 15 assigned to receive inspiratory muscle training (IMT); 15 assigned to received breathing retraining, diaphragmatic breathing and pursed-lips breathing (BRT); 15 assigned to a control group.
                All study groups participated in a conventional stroke rehabilitation programme. For the same period, the IMT and BRT groups trained daily, six times a week, with each session consisting of one half-hour of training for six weeks.
                Each subject underwent pulmonary function and cardiopulmonary exercise tests. Subjects were also assessed for exertional dyspnoea, stages of motor recovery, ambulation status, activity of daily living and quality of life.
                After the training programme, the IMT group had significantly improved forced expiratory volume at 1 second (FEV(1)), forced vital capacity (FVC), vital capacity (VC), forced expiratory flow rate 25-75% (FEF 25-75%) and maximum voluntary ventilation (MVV) values compared with the BRT and control groups, although there were no significant differences between the BRT and control groups (P<0.01). Peak expiratory flow rate (PEF) value was increased significantly in the BTR group compared with the IMT and control groups. The IMT group also had significantly higher peak oxygen consumption (Vo(2peak)) than the BRT and control groups, although there were no significant differences between the BRT and control groups (P<0.001). There was a statistically significant increase in maximum inspiratory pressure (PI(max)) and maximum inspiratory and expiratory pressure (PE(max)) in the BRT group and, PI(max) in the IMT group compared with baseline and the control group. In the IMT group, this was associated with improvements in exercise capacity, sensation of dyspnoea and quality of life.
                Significant short-term effects of the respiratory muscle training programme on respiratory muscle function, exercise capacity and quality of life were recorded in this study.
There is insufficient evidence to support inspiratory muscle training as an effective treatment to improve function after stroke, and no evidence relating to the safety of inspiratory muscle training. Further well-designed RCTs are required.