Effectiveness of combined exercise in people with type 2 diabetes and concurrent overweight/obesity: a systematic review and meta-analysis

OBJECTIVE: To synthesise the available scientific evidence on the effects of combined exercise on glycaemic control, weight loss, insulin sensitivity, blood pressure and serum lipids among patients with type 2 diabetes (T2D) and concurrent overweight/obesity. DESIGN AND SAMPLE: PubMed, EMBASE, Web of Science, the Cochrane library, WANFANG, CNKI, SinoMed, OpenGrey and ClinicalTrials.gov were searched from inception through April 2020 to identify randomised controlled trials (RCTs) that reported the effects of combined exercise in individuals with T2D and concurrent overweight/obesity. METHODS: Quality assessment was performed using the Cochrane Collaboration’s risk of bias tool. The mean difference (MD) with its corresponding 95% CI was used to estimate the effect size. Meta-analysis was performed using Review Manager V.5.3. RESULTS: A total of 10 RCTs with 978 participants were included in the meta-analysis. Pooled results demonstrated that combined exercise significantly reduced haemoglobin A1c (MD=−0.16%, 95% CI: −0.28 to −0.05, p=0.006); body mass index (MD=−0.98 kg/m(2), 95% CI: −1.41 to −0.56, p<0.001); homeostasis model assessment of insulin resistance (MD=−1.19, 95% CI: −1.93 to −0.46, p=0.001); serum insulin (MD=−2.18 μIU/mL, 95% CI: −2.99 to −1.37, p<0.001) and diastolic blood pressure (MD=−3.24 mm Hg, 95% CI: −5.32 to −1.16, p=0.002). CONCLUSIONS: Combined exercise exerted significant effects in improving glycaemic control, influencing weight loss and enhancing insulin sensitivity among patients with T2D and concurrent overweight/obesity.