Abstract / Summary
Abstract Background Rheumatoid arthritis is a chronic, systemic disease in which patients can benefit from physical exercise. We conducted a systematic review and meta‐analysis on the effects of physical training on quadriceps muscle strength in individuals with rheumatoid arthritis. Methods A comprehensive search was conducted in PubMed, Embase, Cochrane, Lilacs, Web of Science, Scopus, and gray literature sources (Google Scholar, OpenGray, and ProQuest). The search was performed from inception to November 20, 2025. The inclusion criteria were: patients diagnosed with rheumatoid arthritis; age above 18 years; both sexes; no restrictions on comorbidities; interventions involving physical training. Two authors independently screened studies and assessed the risk of bias using the Cochrane RoB 2 tool. Quadriceps strength was analyzed via pooled estimates and subgroup analyses. Results Nine randomized clinical trials were included in the systematic review. Eight studies (249 participants in the experimental groups and 208 in the control groups) were included in the meta‐analysis, while one study, Seneca et al. (2015), was included only in the narrative synthesis. The overall meta‐analysis showed a significant improvement in quadriceps strength (standardized mean difference [SMD] = 1.56; 95% confidence Interval [CI]: 0.61 to 2.52; p = 0.001; I 2 = 94%). In subgroup analyses, significant effects were observed for both high‐intensity training (SMD = 0.91; 95% CI: 0.33 to 1.49; I 2 = 66%) and moderate/conventional training (SMD = 3.31; 95% CI: 1.13 to 5.50; I 2 = 98%), with a significant subgroup difference ( p = 0.04); however, this difference was not maintained after excluding studies at high risk of bias ( p = 0.49). Fully supervised programs showed a significant effect (SMD = 2.01; 95% CI: 0.78 to 3.25; I 2 = 95%), while the partially supervised/home‐based subgroup was represented by a single study (SMD = 0.56; 95% CI: 0.19 to 0.92). Significant subgroup differences were also observed according to comparator type ( p = 0.004) and strength measurement method ( p = 0.003), but neither remained significant in sensitivity analyses ( p = 0.49 for both). No significant subgroup difference was found according to intervention duration ( p = 0.55). The planned subgroup analysis according to disease stage could not be performed. In the sensitivity analysis excluding studies at high risk of bias, the overall effect remained significant (SMD = 0.94; 95% CI: 0.43 to 1.45; p = 0.0003; I 2 = 56%). No serious adverse events were reported, although safety outcomes were not systematically assessed across studies. Conclusions Physical training leads to significant improvements in quadriceps strength in patients with rheumatoid arthritis. More standardized protocols are needed to optimize exercise prescription for this population.