Feasibility of High-Intensity Interval Training Before, During, and After Cancer Treatment: A Systematic Review and Meta-Analysis.

purposeTo systematically evaluate the feasibility and safety of high-intensity interval training (HIIT) interventions in cancer populations across the cancer care continuum (before, during, and after cancer treatment).

methodsThis systematic review and meta-analysis followed PRISMA guidelines and was registered in PROSPERO. PubMed, Scopus, and Web of Science were searched from inception to 31 December 2025. Studies were included if they enrolled adults with cancer, implemented a HIIT intervention, and reported feasibility outcomes. Recruitment, adherence, and dropout outcomes were calculated as study-specific proportions with 95% confidence intervals and pooled using random-effects models with REML estimation. Risk of bias was assessed using RoB 2 for RCTs and MMAT for non-randomized studies, while certainty of evidence was evaluated using GRADE.

resultsTwenty-two studies were included, comprising 559 participants in HIIT groups. Pooled recruitment across 20 studies was 0.57 (95% CI: 0.41-0.72), pooled adherence across 21 studies was 0.91 (95% CI: 0.86-0.95), and pooled dropout across 20 studies was 0.11 (95% CI: 0.06-0.16). Recruitment showed considerable heterogeneity, whereas adherence and dropout showed moderate heterogeneity. No statistically significant subgroup differences were observed by study design, intervention setting, treatment phase, or exercise frequency. Adverse events were reported in six studies, with no serious adverse events.

conclusionsHIIT appears feasible and safe for individuals with cancer, particularly after enrolment. However, recruitment remains moderate, and findings should be interpreted cautiously due to heterogeneity, risk of bias, and limited certainty of evidence.