Effects of inspiratory muscle training on walking capacity of individuals after stroke: A double-blind randomized trial

• Published in: Clinical rehabilitation Vol. 35; no. 9; pp. 1247 - 1256
• Main Authors: Vaz, Lorena de Oliveira, Almeida, Juliana de Carvalho, Froes, Karla Simone dos Santos Oliveira, Dias, Cristiane, Pinto, Elen Beatriz, Oliveira-Filho, Jamary
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-09-2021; Sage Publications Ltd
• Subjects: Activities of daily living; Clinical research; Clinical trials; Double-blind studies; Hospitals; Intervention; Quality of life; Rehabilitation; Strength; Stroke; Walking; Gait; respiratory muscle; stroke
• ISSN: 0269-2155; 1477-0873
• DOI: 10.1177/0269215521999591

Objectives:
Identify the effects of inspiratory muscle training (IMT) on walking capacity, strength and inspiratory muscle endurance, activities of daily living, and quality of life poststroke.
Design:
Double-blind randomized trial.
Setting:
The Sarah Network of Rehabilitation Hospitals.
Subjects:
Adult poststroke inpatients with inspiratory muscle weakness.
Interventions:
The Experimental Group (EG) (n = 23) underwent IMT for 30 minutes/day, five times/week over six weeks. The Control Group (CG) (n = 27) performed sham IMT. Both groups underwent standard rehabilitation.
Main measures:
Primary outcome was post-intervention six-minute walking test (6MWT) distance. We also measured maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), inspiratory muscle endurance, activities of daily living (functional independence measure – FIM), and quality of life at baseline and post-intervention. Three months after intervention, we measured MIP, walking capacity and quality of life.
Results:
Baseline characteristics were similar, with mean age 53 ± 11 years and FIM 74 ± 10p. Both groups similarly increased the walking capacity at six weeks (63 vs 67 m, P = 0.803). Compared to the CG, the EG increased the inspiratory endurance (22 vs 7 cmH2O, P = 0.034) but there was no variation in MEP (14 vs 5 cmH2O, P = 0.102), MIP (27 vs 19 cmH2O, P = 0.164), FIM (6 vs 6, P = 0.966) or quality of life (0 vs 0.19, P = 0.493). Gains in both groups were sustained at three months.
Conclusion:
Adding IMT to a rehabilitation program improves inspiratory muscle endurance, but does not further improve MIP, 6-MWT distance, activities of daily living or quality of life of individuals after stroke beyond rehabilitation alone.
Registered in Clinical Trials, NCT03171272.