Effects of aerobic exercise on selected physiological parameters and quality of life in patients with type 2 diabetes mellitus

BACKGROUND The aim of this study was to evaluate the effects of an 8-week aerobic exercise program on physiological parameters and quality of life in patients with type 2 diabetes mellitus. METHODS Patients attending a diabetes clinic participated in this randomized control trial. They were randomly assigned to an intervention or control group by ballot. The intervention group, in addition to regular conventional treatment, received individually prescribed aerobic exercise for 30 minutes, at 50%-75% of maximum heart rate three times weekly. Main outcome measures included fasting blood sugar, glycosylated hemoglobin (HbA(1c)), high-density lipoprotein, low-density lipoprotein, and a World Health Organization quality of life questionnaire (WHOQoL-BREF). Data analysis involved paired and unpaired t-tests and mixed-design two-way analysis of variance. RESULTS Eighteen patients with type 2 diabetes and of mean age 46.22 ± 9.79 years participated in the study. Mean duration since onset of diabetes in the intervention and control groups was 4.44 ± 3.33 years and 3.92 ± 2.66 years, respectively. Both groups were similar for duration since onset, baseline physiological parameters, and quality of life. Within-group comparison did not show any significant differences (P > 0.05) for HbA(1c), fasting blood sugar, low-density lipoprotein, or high-density lipoprotein. The intervention group improved significantly (P < 0.05) in their postexercise quality of life compared with baseline. Between-group comparison did not show any significant differences in physiological parameters or quality of life. CONCLUSION Patients with type 2 diabetes improved in fasting blood sugar, low-density lipoprotein, high-density lipoprotein, and quality of life following 8 weeks of aerobic exercise training. These perceived improvements were not reflected by statistically significant differences in between-group comparison for any parameters.