Repercussões do treinamento muscular inspiratório na tolerância ao exercício avaliada através do teste do degrau de seis minutos

Abstract

Background: The inspiratory muscle training (IMT) is an option for increased respiratory muscle strength, with several positive effects in various populations. Objective: Evaluate exercise tolerance, respiratory muscle strength and thickness and diaphragmatic mobility before and after IMT protocol of 9 weeks. Methodology: In a controlled clinical trial, randomized, double-blind, 24 participants were divided into two groups: Training (G55%) and control (G10%). It was performed the six-minute step test (TD6), manometer, spirometry and ultrasound of the diaphragm. The training group (G55%) held the protocol with 55% MIP load and the control group (G10%) with 10%. All trained 2x a day, 6 times per week for 9 weeks with reassessment of MIP every two weeks for load adjustment. Data were analyzed using the SPSS 20.0 program with 5% significance level. Results: There was a significant difference in the amount of steps ascended (G55%: p=0.03; G10%: p=0.001) inspiratory muscle strength (G55%: p=0.02; G10%: p=0.01), variation heart rate (G10%: p=0.025) and perception of dyspnea (G10%: p=0.032). There was no significant difference in expiratory muscle strength (G55%: p=0.089; G10%: p=0.242), thickness CRF (G55%: p=0.070; G10% p=0.857), thickness of CPT (G55%: p=0.480; G10%: p =0.551) and mobility (G55%: p=0.317; G10%: p=0.057). There was only intergroup difference in MIP in the post training time (p=0.032). Conclusion: Protocols with mild and moderate loads promote improvement in inspiratory muscle strength and performance of the TD6, however there was no intergroup difference. The protocol used was not able to promote morphological changes in the diaphragm.