| Abstract: | INTRODUCTION: High-intensity interval training (HIIT) is considered a time-efficient strategy to improve metabolic health. We performed a systematic meta-analysis to assess the effects of HIIT on inflammatory markers and adipo-cytokines compared with control conditions (CON) or moderate-intensity continuous training (MICT) in individuals with metabolic disorders. METHODS: Up to January 2020, electronic databases were searched for HIIT interventions based on populations with metabolic disorders including diabetes, metabolic syndrome, polycystic ovary syndrome, non-alcoholic fatty liver disease or overweight/obesity, with outcome measurements that included IL-6, TNF-α, CRP, leptin or adiponectin and training ≥2 weeks. Random-effects models were used to aggregate a mean effect size (ES), 95% confidence intervals (Cis), and potential moderators were explored. RESULTS: Twenty-nine studies involving 841 participants were included in the meta-analysis. HIIT improved circulating adiponectin (P = .02), leptin (P = .02), and TNF-α (P = .003) when compared to CON. There were no differences between groups in IL-6 and CRP. Intervention duration was a significant moderator for the effect of HIIT on IL-6, and leptin (P < .05). CONCLUSION: High-intensity interval training improves circulating TNF-α, leptin and adiponectin, thereby indicating that it may be an effective and time-efficient intervention for controlling low-grade inflammation in individuals with metabolic disorders. |
