Effects of blood flow restriction exercise on hemostasis: a systematic review of randomized and non-randomized trials.

Abstract

BackgroundBlood flow restriction (BFR) exercise has shown to induce a positive influence on bone metabolism and attenuate muscle strength loss and atrophy in subjects suffering from musculoskeletal weakness. Despite the known benefits of BFR exercise, it remains unclear whether or not the pressurization of blood vessels damages the endothelial cells or increases risk for formation of thrombi. Thus, the effects of BFR exercise on coagulation, fibrinolysis, or hemostasis, remains speculative.ObjectiveThe aim of the present study was to perform a systematic review of the short and long- term effects of BFR exercise on blood hemostasis in healthy individuals and patients with known disease (ie, hypertension, diabetes, obesity, and ischemic heart disease).Data SourcesA systematic review of English and non-English articles was conducted across PubMed, Science Direct, and Google Scholar databases, including reference lists of relevant papers. Study quality assessment was evaluated using the modified version of Downs and Black checklist. Search results were limited to exercise training studies investigating the effects of BFR exercise on blood hemostasis in healthy individuals and patients with disease. Level of evidence was determined according to the criteria described by Oxford Center for Evidence-Based Medicine.Study selectionOnly randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs) that examined the effects of exercise with BFR exercise vs exercises without BFR on blood hemostasis in healthy individuals and patients were included.Data extractionNine studies were eligible (RCT =4; NRCT =5).ResultsThe average score on the Downs and Black checklist was 11.22. All studies were classified as having poor methodological quality wherein the level of evidence provided in all reviewed studies was level IIb only (ie, poor quality RCTs).ConclusionConsidering the limitations in the available evidence, firm recommendations cannot be provided.