The safety and efficacy of high-intensity interval training (HIIT) in post-stroke patients with moderate functional impairment: a systematic review and meta-analysis

Objective This study aimed to compare the efficacy and safety of high-intensity interval training (HIIT) versus conventional rehabilitation for improving lower limb function in post-stroke patients. Methods A comprehensive literature search was conducted in PubMed, EMBASE, Web of Science, and Scopus from inception to January 2025. Only randomized controlled trials (RCTs) involving adults in post-stroke rehabilitation published in English were included, while grey literature was excluded. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. The primary outcomes were 6-min walk test (6MWT), Self-Selected Speed (SSS) and the Fastest Speed (FS). The secondary outcomes were peak oxygen uptake (Peak VO 2 ) and SF-36 scores. The experimental group received high-intensity interval training (which involved robotic-assisted, cycling-based, or treadmill protocols targeting ≥60% of Peak VO₂), and the control group received standard care or regular exercise. Results This meta-analysis included 10 studies. The results showed that high-intensity interval training has demonstrated significant improvements in walking ability and cardiopulmonary function compared with controls. High-intensity interval training had positive effects on 6MWT [ SMD = 0.25, 95% CI (−0.01, 0.52)], SSS [ SMD = 0.65, 95% CI (0.26, 1.03)], FS [ SMD = 0.49, 95% CI (0.10, 0.88)], SF-36 scores [ SMD = 0.67, 95% CI (0.04, 1.21)] and Peak VO₂ [ SMD = 0.29, 95% CI (0.04, 0.54)] in stroke patients. According to the analysis, HIIT participants demonstrated better rehabilitation outcomes in walking capacity, cardiorespiratory function and quality of life. Conclusion HIIT may be a safe and effective therapy for specific post-stroke patients, but more high-quality research is needed to confirm its efficacy and optimize protocols. Systematic review registration This systematic review was registered in PROSPERO (Unique Identifier: CRD42025637166). The protocol can be accessed at: https://www.crd.york.ac.uk/PROSPERO/view/CRD42025637166 .