To conduct a meta-analysis of randomized-controlled trials in order to assess the effects of regular physical activity on glycemic and lipid control in Chinese type 2 diabetic patients.

All randomized controlled trials (RCTs) that evaluated the effects of physical activity intervention (duration≥3 months) in Chinese type 2 diabetic patients in China BioMedical literature on disc (CBMdisc) (1978 to February 2011), Chinese Science and Technology Academic Journal (Chongqing VIP) (1989 to February 2011), Wanfang data (1982 to February 2011), China Journals Full text Database (CJFD) (1994 to February 2011), and Papers on Academic Conference of China (1998 to February 2011) were retrieved. And also the reference lists of all articles collected were checked to ensure that no relevant suitable studies were missed. The articles concerning comparisons between regular physical activity combined with usual treatments and usual treatments combined with irregular physical activity or alone were included. The trials were selected and assessed by two authors independently. Continuous data were calculated as mean differences (MD). Random-effects model and fixed-effects model were used to perform meta-analysis for with and without heterogeneity respectively.

Only twenty papers containing 23 RCTs were available for pooling involving 1444 participants. Compared with the control, the physical activity intervention significantly improved glycemic control as indicated by a decrease in glycated haemoglobin A1c (HbA1c) levels of 1.18% (weighted MD(WMD)=-1.18, 95% confidence interval (CI) -1.67 to -0.69; P<0.01). And there was a reduction in triglycerides (TG) and total cholesterol (TC) levels by 0.27 mmol/L (-0.27, 95%CI: -0.36 to -0.19) and 0.78 mmol/L (WMD=-0.78, 95%CI: -0.88 to -0.68) respectively with physical activity intervention. Also high-density lipoprotein cholesterol (HDL-C) increased by 0.17 mmol/L (WMD=0.17, 95%CI: 0.12 to 0.23) and low-density lipoprotein cholesterol (LDL-C) decreased by 0.48 mmol/L (WMD=-0.48, 95%CI: -0.64 to -0.32).

The results suggest that regular physical activity decreases HbA1c, TG, TC and LDL-C and increases HDL-C in Chinese type 2 diabetic patients, additional high quality of randomized-controlled trials are needed on these topics.

Diabetes mellitus, type 2; Sports; Meta-analysis; Randomized control trial