Abstract
BACKGROUND: Many patients with amyotrophic lateral sclerosis (ALS) experience respiratory failure. The use of respiratory muscle training exercises can improve the respiratory function of these patients. This study aimed to evaluate the effect of inspiratory muscle training (IMT) on respiratory muscle function in ALS patients. METHODS: In the current randomized controlled clinical trial study, 22 patients were randomly divided into intervention (n = 11) and control groups (n = 11). In the control group, patients used only chest-opening training and diaphragm exercises. Patients in the intervention group used IMT in addition to controlled exercises (chest opening training and diaphragm exercises). Respiratory function by spirometry and monitoring of maximum inspiratory and expiratory pressure, functional capacity with a 6-minute walk test, and arterial blood gases were also assessed by ABG analysis at baseline and after 8 weeks. A comparative analysis of variables was performed with a student t-test, considering type 1 error (α = 0.05) using SPSS 27 software. RESULTS: The indexes included maximal inspiratory pressure (PImax) (P = 0.000) and maximal expiratory pressures PEmax (P = 0.002). The strength of breathing muscles index (S-index) (P = 0.002) had a significant increase before and after rehabilitation in both groups (P ˂ 0.05). In intergroup analysis, the only factor with a significant increase was PImax (P = 0.019). CONCLUSION: The use of IMT, along with chest opening training and diaphragm exercises, can cause a relative improvement of the respiratory muscles' function indexes, especially PImax in ALS patients. More clinical trials are required.