Effect of respiratory muscle training on symptoms of fibromyalgia: a systematic review with meta-analysis

This systematic review with meta-analysis aimed to investigate the effects of respiratory muscle training (RMT) on symptoms of fibromyalgia (FM). Searches were conducted in Medline/PubMed, EMBASE, Web of Science, SCOPUS, CINAHL, and PEDro for studies published up to November 2025. Randomized controlled trials comparing RMT to control conditions in individuals with FM were included. Risk of bias was assessed using the Cochrane tool, and the quality of evidence was analyzed using the GRADE. Mean differences (MD) and 95% confidence interval (CI) were calculated. Four studies were included; with meta-analyses conducted on two of them. RMT was superior to the control group at improving pain (MD: -2.98; 95% CI: -3.17 to -1.60), quality of life (MD: -1.09; 95% CI: -1.61 to -0.56), fatigue (MD: -1.16; 95% CI: -1.69 to -0.63), anxiety (MD: -0.60; 95% CI: -1.10 to -0.03), and sleep quality (MD: -3.93; 95% CI: -7.06 to -0.80), and maximal occlusion pressure (MD: 2.08; 95% CI: 1.58 to 2.58). However, the certainty of evidence for these findings was very low according to the GRADE approach. In conclusion, RMT may lead to improvements in several FM-related symptoms, but the current evidence is insufficient for clinical recommendations, and high-quality trials are urgently needed.Protocol registration: https://www.crd.york.ac.uk/prospero identifier is CRD42023445488.