Blood flow restriction training for lower-limb function, walking and functional recovery after stroke: a systematic review and meta-analysis

Background Blood flow restriction training (BFRT) is increasingly used as a low-load rehabilitation strategy after stroke, but the magnitude, clinical relevance, and certainty of its effects remain uncertain. We evaluated the effects and safety of BFRT on lower-limb function and mobility after stroke. Methods PubMed, Embase, Web of Science Core Collection, CENTRAL, CNKI, Wanfang, VIP, and SinoMed were searched from inception to June 10, 2026. Randomized controlled trials evaluating lower-limb BFRT in adults after stroke were included. Risk of bias was assessed using RoB 2, certainty using GRADE, and random-effects meta-analyses were performed. Results Nineteen randomized controlled trials were included. BFRT improved Fugl-Meyer Assessment of the Lower Extremity scores (10 studies, 646 participants; MD = 2.14 points, 95% CI 0.74 to 3.54) and Berg Balance Scale scores (8 studies, 581 participants; MD = 4.72 points, 95% CI 1.62 to 7.82). The 10-meter walk test analysis showed higher walking speed (4 studies, 322 participants; MD = 0.14 m/s, 95% CI 0.03 to 0.25), but the estimate attenuated after eligible grey literature was included (6 studies, 410 participants; MD = 0.09 m/s, 95% CI − 0.03 to 0.21). Six-minute walk distance increased by 8.01 m (5 studies, 271 participants; 95% CI 2.31 to 13.71). No clear pooled effects were observed for Timed Up and Go, sit-to-stand performance, cadence, or standard full-scale Barthel Index/Modified Barthel Index scores. FMA-LE and 6MWT effects were below reported clinically important thresholds; the BBS estimate was close to an approximately 5-point reference, with its confidence interval spanning effects below and above that threshold. Certainty was moderate for 6MWT, low for FMA-LE, and very low for BBS and 10MWT walking speed. No BFRT-related serious adverse or thrombotic events were reported among studies with explicit safety information, although reporting was limited. Conclusion BFRT may improve selected lower-limb outcomes after stroke, but clinical importance remains uncertain for several outcomes and certainty ranges from moderate to very low. Better-designed trials with standardized BFRT protocols and more complete safety reporting are needed. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/view/CRD420261477739 , PROSPERO CRD420261477739.