Objective:To explore the effect of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the aerobic capacity of middle-aged and elderly patients with type 2 diabetes.Methods:A total of 95 patients with type 2 diabetes (aged 45 to 70 years) were randomly divided into an HIIT group ( n=35), an MICT group ( n=35) and a sedentary control group (CON group) ( n=25). All of the subjects maintained their daily habits, but the HIIT and MICT groups performed their corresponding exercise using a bicycle ergometer 4 times/week for 8 weeks. Before and after the 8 weeks, each subject′s maximum oxygen uptake (VO 2max) was measured using a graded exercise test. Results:Eighty-three of the subjects (87.4%) completed the study. The follow-up loss rate in the HIIT group was 13% and in the MICT group it was 14%. After the intervention, the average VO 2max had increased by (11.5±2.3)% in the HIIT group and (8.1±1.9)% in the MICT group, a difference which is not significant. Conclusion:Either HIIT or MICT is feasible, well tolerated, safe and effective for improving the aerobic capacity of middle-aged and elderly patients with type 2 diabetes.