The effects of low-intensity resistance training with blood flow restriction versus traditional resistance exercise on lower extremity muscle strength and motor functionin ischemic stroke survivors: a randomized controlled trial

ABSTRACTBackground Blood flow restriction (BFR) training can temporarily reduce cortical GABA concentrations and increase the size of motor volleys to deafferented muscles, which can promote motor recovery in stroke survivors.Objective To determine the effect of low-intensity resistance training with BFR (LIRT-BFR) on lower extremity muscle strength, balance, functional mobility, walking capacity, gait speed, anxiety, and depression in stroke survivors and to compare the results with high-intensity resistance training (HIRT).Method It was a two-arm, single-blinded, randomized controlled trial in which 32 ischemic stroke participants were randomly allocated to LIRT-BFR or HIRT group. The LIRT-BFR group received low load resistance training (40% of 1-Repetition Maximum (1-RM)) with BFR, whereas HIRT group received high load resistance training (80% of 1-RM). The 6-Minute Walk Test (6-MWT), five-time sit-to-stand test (5TSTST), Timed Up and Go (TUG) test, and Barthel index were the primary outcome measures. The secondary outcome measures included gait speed (m/s), stride length (cm), cadence (steps/min), and Hospital Anxiety and Depression.Results All the primary and secondary outcome measures were significantly improved in both groups (p < 0.05). The LIRT-BFR group showed a slightly greater, but non-significant, improvement as compared to the HIRT group in terms of mean change observed in 6-MWT (81 m vs 62 m), 5TSTST (−5.27 vs −4.81), gait speed (0.19 vs 0.12), stride length (18 vs 13), and cadence (8 vs 6). No adverse event was reported.Conclusion LIRT-BFR produced a significant improvement in muscle strength, balance, walking capacity, and anxiety and depression in ischemic stroke patients, and the improvement are comparable to HIRT.Clinical Trial Registration NCT05281679KEYWORDS: Strokewalking capacitybalancegait impairmentstrength training Highlights The adjunct of BFR to LIRT produced a significant improvement in muscle strength, balance walking capacity, and anxiety and depression in ischemic stroke patients.The improvements produced by LIRT-BFR are comparable to HIRT.BFR training was found to be safe and a useful adjunct for stroke survivors to augment the effects of exercise on muscle activity.Abbreviations LIRT-BFR=Low-intensity resistance training with BFR (LIRT-BFR).HIRT=High-intensity resistance training without BFR.GABA=Gamma-aminobutyric acidVEGF=Vascular endothelial growth factorBDNF=Brain-derived neurotrophic factor1-RM=One repetition maximum5TSTST=Five-time Sit-to-Stand Test6MWT=6-minute walk testTUG=Timed up and go testBI=Barthel indexHADS=Hospital Anxiety and DepressionAcknowledgmentsThe authors would like to show their gratitude to Professor Suleyman Yalcin City hospital for providing the infrastructure and permission to conduct the research in the hospital-based setting.Authors ContributionsI.A. contributed to study conceptualization, Planning, Methodology, data curation, data compilation, investigation, formal analysis, investigation, writing – original draft, and visualization; R.M. contributed to study conceptualization, supervision, methodology, formal analysis, and, writing- review & editing; B.E. contributed to supervision, methodology, writing – review & editing of the manuscript. All authors read the final draft of the manuscript and gave approval for its submission or publication.Ethics approvalThis randomized controlled trial was approved by the institutional and ethical review board of the university (Protocol No: E-74555795-050.01.04-335,759) and was prospectively registered at ww.clinicaltrials.gov (identifier: NCT05281679).Data availability statementAll data relevant to the study are included in the article or uploaded as supplementary information. Further information is available upon reasonable request.Disclosure statementNo potential conflict of interest was reported by the author(s).Correction StatementThis article has been corrected with minor changes. These changes do not impact the academic content of the article.Additional informationFundingThe authors have not declared a specific grant for this research from any funding agency in the public, commercial, or not-for-profit sectors.