Comparative Efficacy of Different Exercise Modes on Inflammatory Markers in Patients With Type 2 Diabetes Mellitus: A Systematic Review With Pairwise and Network Meta‐Analyses

Exercise training can reduce chronic low-grade inflammation; however, the most effective mode of exercise for lowering inflammation in patients with type 2 diabetes mellitus (T2D) is unknown. Therefore, we performed a systematic review with pairwise and network meta-analyses to determine the efficacy of different modes of exercise training for improving inflammation in patients with T2D. A systematic literature search was conducted in the PubMed, Web of Science, and Scopus from inception to May 2024 using four main key words including "exercise," "cytokines," "type 2 diabetes," and "randomization." Randomized control or clinical trials investigating the effects of any exercise training mode, including aerobic training (AT), resistance training (RT), AT + RT, high-intensity interval training (HIIT), and HIIT + RT on inflammatory markers including interleukin-6 (IL-6), TNF-α, C-reactive protein (CRP), leptin, or adiponectin in patients with T2D were included. Standardized mean differences (SMD) and 95% confidence intervals (CIs) were calculated using random effects models. Overall, 60 studies involving 3339 patients with T2D were included. Compared to control, exercise training effectively reduced IL-6 [SMD: -0.58], TNF-α [SMD: -0.62], CRP [SMD: -0.78], and leptin [SMD: -0.27], and increased adiponectin [SMD: 0.35]. Based on network meta-analysis, AT reduced IL-6, TNF-α, and leptin and increased adiponectin; and AT + RT reduced IL-6, TNF-α, and CRP, and increased adiponectin. However, RT, HIIT, and HIIT + RT did not change any inflammatory markers as compared with controls. Exercise training is an effective approach for lowering chronic low-grade inflammation in patients with T2D; specifically, AT and AT + RT appear to be more effective than RT, HIIT, or HIIT + RT.