Chronic Obstructive Pulmonary Disease (COPD) is an inflammatory and progressive condition that causes ventilation limitation, reducing the quality of life of individuals due to decreased exercise tolerance. Due to the characteristics of the disease, resistance exercise for this population is limited to low (LB) or moderate (MB) loads. In this context, resistance training (RT) + blood flow restriction (BFR) can provide gains similar to those of training with high loads and has been incorporated into inspiratory muscle training (IMT) as an intervention strategy for COPD management.

Evaluate the acute effects of IMT and RT with or without BFR on: maximum inspiratory pressure (MIP), respiratory rate (RR), peripheral oxygen saturation (SpO2), and dyspnea in individuals with COPD.

This is an experimental clinical trial with a crossover design. The sample consisted of 14 elderly individuals (67.5 ± 1.76 years) of both sexes, diagnosed with mild, moderate, or severe COPD, who were initially evaluated for body composition, ankle-brachial index (ABI), determination of arterial occlusion pressure (AOP), evaluation of inspiratory muscle strength, and 1RM test. They were then subjected to 3 experimental protocols: 1) RT with low load (30% 1RM) + IMT (30% MIP); 2) RT with low load (30% 1RM) + BFR (50% of AOP) + IMT (30% MIP); and 3) RT with moderate load (50% 1RM) + IMT (50% MIP), with a wash-out period of 48-72 hours. Respiratory rate (RR), SpO2, and dyspnea were assessed before, immediately after, and 10 minutes post-exercise, while MIP was measured after each protocol. Data were analyzed using the Statistical Package for the Social Sciences (SPSS – 26.0), with a significance level set at P = 0.05.

There was a significant reduction in respiratory rate (RR) when comparing pre- and 10-minute post-intervention in all protocols, and in the intergroup comparison, the TRCB+RFS+IMT protocol showed a lower value than TRCB+IMT (P = 0.001). No differences were found in SpO2 between the groups; however, an increase was observed in the intragroup comparison between pre- and 10-minute post-intervention in all protocols. No difference was found between pre- and post-MIP values in the protocols (P > 0.05), but in the intergroup analysis, an increase was observed in TRCB+RFS+IMT (P = 0.010) compared to TRCB+IMT. A significant reduction in dyspnea was observed in the TRCM+IMT group (P = 0.001) compared to TRCB+IMT and TRCB+RFS+IMT.

IMT associated with RT, with or without BFR, was able to reduce respiratory rate (RR) and dyspnea, as well as increase SpO2 in individuals with COPD. However, the only protocol that showed a significant increase in MIP was TRCB+RFS+IMT, demonstrating greater effectiveness. Further studies are needed to explore the potential of these protocols in specific samples according to the severity of symptoms, for better homogenization of results.

This study demonstrates that IMT combined with RT, with or without BFR, effectively improves dyspnea and respiratory variables, highlighting its potential application in physiotherapy for COPD treatment.