High-intensity interval training after stroke: A mixed-methods systematic review and meta-analysis of safety, feasibility and acceptability.

ObjectiveTo synthesise evidence regarding the safety, feasibility and acceptability of high-intensity interval training in adults post-stroke.Data sourcesA systematic literature search using eight major databases from inception to January 2025.Review methodsStudies of any design, involving adults post-stroke, reporting on safety, feasibility and/or acceptability of any type of high-intensity interval training, were eligible. Methodological quality was assessed using the Effective Public Health Practice Project or the Mixed Methods Appraisal Tool, as appropriate. Meta-analyses of adverse events and dropouts were undertaken on data from randomised controlled trials. GRADE methodology was used to categorise the level of certainty of the evidence from each meta-analysis.ResultsTwenty studies plus one follow-up and a cost analysis, involving 658 participants, were included. Methodological quality varied. High-intensity interval training was mainly conducted individually and in supervised settings. There were no fatalities related to high-intensity interval training. There was low-moderate certainty of no difference in the risk of adverse events, whether these were intervention-related, non-intervention related or unclear. Average attendance at high-intensity interval training sessions was 94.4%. Reporting on acceptability of high-intensity interval training was scarce, but where reported participants' experiences were generally favourable.ConclusionThis systematic review found low-moderate certainty evidence that high-intensity interval training can be safe and feasible for carefully selected, generally younger, mildly affected, male stroke survivors in the chronic stage, supervised by trained professionals in controlled settings. Future studies should investigate experiences of high-intensity interval training and explore its use in a wider stroke population and range of settings.