Effectiveness of multi-component exercise in individuals with type 2 diabetes: a systematic review and meta-analysis

Objective: This meta-analysis aimed to explore the effects of multi-component exercise interventions on glycemic and lipid metabolism, physical fitness, and cognitive function in individuals with type 2 diabetes mellitus (T2DM). Methods: From inception to December 28, 2024, PubMed, Web of Science, Cochrane, and Elsevier databases were systematically searched for randomized controlled trials (RCTs) investigating multi-component exercise interventions for T2DM. A total of 37 articles, comprising 3,201 participants, were included. Primary and secondary outcome measures were categorized, summarized, and analyzed using RevMan 5.4 software. Results: Compared to control groups, multi-component exercise interventions produced statistically significant improvements across all measured outcomes in individuals with T2DM: (1) Glycemic control: HbA1c (standard mean difference (SMD) = -0.52, 95% confidence interval (CI) -0.76 to -0.28); fasting blood glucose (SMD = -0.53, 95% CI -0.93 to -0.12). (2) Lipid metabolism: high density lipoprotein (HDL) (SMD = 0.32, 95% CI 0.21-0.44); low density lipoprotein (LDL) (SMD = -0.21, 95% CI -0.33 to -0.09); triglycerides (SMD = -0.18, 95% CI -0.30 to -0.06). (3) Physical fitness: upper limb strength (SMD = 0.67, 95% CI 0.51-0.83); lower limb strength (SMD = 0.56, 95% CI 0.10-1.02); peak oxygen consumption (SMD = 0.62, 95% CI 0.31-0.93); body mass index (BMI) (SMD = -0.38, 95% CI -0.67 to -0.09). (4) Cognitive function: overall cognitive performance (SMD = 0.34, 95% CI 0.18-0.50). (5) Quality of life: vitality (SMD = 0.37, 95% CI 0.09-0.64); physical functioning (SMD = 0.48, 95% CI 0.20-0.75); mental health (SMD = 0.35, 95% CI 0.07-0.63); general health (SMD = 0.34, 95% CI 0.06-0.61). Quality assessment indicated that the included studies were of high overall quality. Egger's regression analysis did not reveal significant publication bias. Conclusions: Multi-component exercise interventions significantly improved glycemic and lipid metabolism, physical fitness, and cognitive function in individuals with T2DM. These findings support the clinical value of incorporating multi-component exercise programs-particularly those performed at least three times per week and lasting 6 months or longer-into diabetes management strategies.