The effect of high intensity interval training on inflammatory markers in patient with type 2 diabetes: a systematic review and meta-analysis

 Type 2 diabetes is associated with increased systemic inflammation that may be increased cardiovascular diseases for which exercise training is a potential therapy. The effects of high intensity interval training (HIIT) on inflammatory markers in Type 2 diabetes patients, however, require further elucidation. We therefore performed a systematic review and meta-analysis to investigate the effect of HIIT on inflammatory markers in Type 2 diabetes patients.

 PubMed, Scopus, and Web of Science were searched up to May 2022 for HIIT vs. Control or only HIIT studies on inflammatory makers i.e. CRP, IL-6 and TNF-α in Type 2 diabetes patients. The search was performed using the HIIT, inflammation and type 2 diabetes keywords. Standardized mean difference (SMD) effect sizes and 95% confidence intervals were calculated using CMA2 software.

Among the 257 extracted studies, 11 studies including 257 participants (143 women and 114 men) with an age range of 44 to 71 years were included in the meta-analysis. HIIT was beneficial for promoting a reduction in TNF-a [-0.62 (95% CI: -1.85 to -0.13), p = 0.01] and CRP [-0.65 (95% CI: -1.21 to -0.08), p = 0.02]. However, there were no significant evidence for an effect of HIIT on IL-6 [-0.31 (95% CI: -0.70 to -0.06), p = 0.10] in Type 2 diabetes patients.

 These results suggest that HIIT could induce improvements inflammatory cytokines as well as CRP in Type 2 diabetes patients.