Home-based Respiratory Training After Stroke

Weakness of the respiratory muscles demonstrated by individuals with stroke, may generate important symptoms, such as fatigue and dyspnea. Since adequate strength of the inspiratory and expiratory muscles is required, mainly when performing physical activities, rehabilitation interventions for stroke subjects should include respiratory training. This study will test the hypothesis that home-based combined training of the inspiratory and expiratory muscles is effective in improving strength of the inspiratory and expiratory muscles, endurance of the inspiratory muscles, dyspnea, walking capacity, and ocurrence of respiratory complications after stroke. For this clinical trial, people after stroke will be randomly allocated into either experimental or control/sham groups. The experimental group will undertake training of the inspiratory plus expiratory muscles with the Orygen Dual Valve device, regulated at 50% of the subjects' maximal inspiratory and expíratory pressure values, seven times/week over eight weeks during 40 minutes/day. The control group will undertake the same protocol, but the participants will receive the devices without resistance. At baseline, post intervention, and four weeks after the cessation of the intervention, researchers blinded to group allocations will collect the following outcome measures: maximal inspiratory and expiratory pressures, inspiratory endurance, dyspnea, walking capacity, and ocurrence of respiratory complications.

Rationale: Weakness of the respiratory muscles demonstrated by individuals with stroke, may generate important symptoms, such as fatigue and dyspnea. Since adequate strength of the inspiratory and expiratory muscles is required, mainly when performing physical activities, rehabilitation interventions for stroke subjects should include respiratory training.

Aim: This study will test the hypothesis that home-based combined inspiratory muscular training (IMT) plus expiratory muscular training (EMT) program is effective in improving strength of the inspiratory and expiratory muscles, endurance of the inspiratory muscles, dyspnea, walking capacity, and ocurrence of respiratory complications after stroke.

Design: For this prospective, double-blinded, randomized clinical trial, people after stroke will be randomly allocated into either experimental or control/sham groups. The experimental group will undertake training of the inspiratory plus expiratory muscles with the Orygen Dual Valve, regulated at 50% of the subjects' maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) values, seven times/week over eight weeks during 40 minutes/day. The control group will undertake the same protocol, but the participants will receive the devices without resistance. At baseline, post intervention, and four weeks after the cessation of the intervention, researchers blinded to group allocations will collect all outcome measures.

Study outcomes: Primary outcomes will be MIP. Secondary outcomes will include MEP, inspiratory endurance, dyspnea, walking capacity, and ocurrence of respiratory complications.

Eligibility Criteria:
Inclusion Criteria:

Stroke survivors will be eligible if they: were \>3 months and \<5 years after their last episode of stroke; were \>20 years of age; their maximal inspiratory pressure was \<80 cmH2O or maximal expiratory pressure was \<90 cmH2O \[18\]; were not undertaking any respiratory training; and were able to provide informed consent.

Exclusion Criteria:

Subjects will be excluded if they had cognitive deficits, facial palsy, associated respiratory diseases, or unstable conditions which might prevent measurement or training; or undergone thoracic or abdominal surgery.