Yineng Tan, Jianyu Gan, Leyi Jiang, Huakun Zheng, Yundi Zhang, Limingfei Zhou, Dapeng Bao, Junhong Zhou
BackgroundLow-intensity resistance training with blood flow restriction (LIRT-BFR) may improve musculoskeletal function, but its effects in musculoskeletal disorders remain uncertain.ObjectiveTo examine LIRT-BFR effects on lower-limb muscle size, strength, and mobility in musculoskeletal disorders, and explore potential effect modifiers.MethodsFive databases (PubMed, Cochrane Library, Web of Science, SPORTDiscus, EMBASE) were searched from inception to November 20, 2025. Randomized controlled trials involving adults with musculoskeletal disorders comparing LIRT-BFR to control or active interventions were included. Two reviewers independently screened studies and extracted data. Random-effects meta-analyses were conducted, and certainty of evidence was assessed using the GRADE approach.ResultsSixteen trials (638 participants) were included. Compared with non-exercise controls, LIRT-BFR significantly improved lower-limb muscle strength (g = 1.20, 95% CI [0.54, 1.87]), muscle size (g = 1.65, 95% CI [0.88, 2.43]), and lower-limb functionality (TUG: g = -0.73, 95% CI [-1.21, -0.24]; TST: g = 1.85, 95% CI [1.19, 2.52]). Compared with LIRT alone, LIRT-BFR improved muscle strength (g = 0.56, 95% CI 0.08-1.04) and timed-stands performance (g = 0.86, 95% CI 0.44-1.28). No advantage over MHIRT was observed for muscle strength (g = -0.10, 95% CI -0.48 to 0.28) or timed-stands performance (g = -0.50, 95% CI -1.01 to 0.01). Exploratory analyses showed favorable point estimates for 12-18 sessions and non-failure protocols. Certainty of evidence ranged from moderate to very low across comparator-specific outcomes.ConclusionsLIRT-BFR improves lower-limb muscle and functional outcomes relative to non-exercise controls and may provide additional benefits over LIRT for selected outcomes. No advantage over MHIRT was identified. Clinical heterogeneity, wide prediction intervals, and risk of bias warrant cautious interpretation.