Abstract: BACKGROUND: The occurrence and development of obesity are closely related to microcirculation dysfunction. Improving microcirculation dysfunction is of great significance to obese people. Studies have shown that both aerobic exercise and full-body vibration training can improve microcirculation dysfunction. However, most existing research focuses on single exercise modalities, with insufficient exploration of combined intervention studies.
OBJECTIVE: To compare the effects of 8-week aerobic exercise and aerobic exercise combined with full-body vibration training on the microcirculation function of obese college students. 
METHODS: Sixty obese college students (with a body fat percentage of ≥ 28% for females and ≥ 20% for males) were recruited and divided into three groups using the matching grouping method: The control group (n=20) did not undergo systematic exercise training; the aerobic exercise group (n=20) received 8 weeks of aerobic jogging (4 times a week, 60 minutes each session), and the combined exercise group (n=20) received 8 weeks of aerobic exercise combined with full-body vibration training (4 times a week, 60 minutes each session, including 51 minutes of aerobic jogging and 9 minutes of full-body vibration training). Before and after exercise, microvascular reactivity, transcutaneous partial pressure of oxygen, muscle oxygen saturation, as well as the levels of serum nitric oxide, endothelial nitric oxide synthase and endothelin-1 were detected in the three groups of subjects.
RESULTS AND CONCLUSION: (1) After exercise, microvascular perfusion heat value, blood cell concentration heat value, blood cell migration velocity heat value, transcutaneous oxygen partial pressure, and muscle oxygen saturation in the aerobic exercise group and the combined exercise group were all higher than those in the control group (P < 0.05), and those in the combined exercise group were all higher than those in the aerobic exercise group (P < 0.05). The basal values of microvascular blood perfusion volume and blood cell migration velocity in the combined exercise group after exercise were higher than those before exercise (P < 0.05). The heated values of microvascular blood perfusion volume, blood cell concentration, and blood cell movement speed, transcutaneous oxygen partial pressure and muscle oxygen saturation after exercise in the aerobic exercise group and the combined exercise group were all higher than those before exercise (P < 0.05, P < 0.01). (2) After exercise, the levels of serum nitric oxide, endogenous nitric oxide synthase and nitric oxide/endothelin 1 in the aerobic exercise group and the combined exercise group were all higher than those in the control group (P < 0.05), while the levels of serum endothelin 1 were both lower than that in the control group (P < 0.05). The levels of serum nitric oxide, endogenous nitric oxide synthase and nitric oxide/endothelin in the combined exercise group were higher than those in the aerobic exercise group (P < 0.05), while the level of serum endothelin 1 was lower than that in the aerobic exercise group (P < 0.05). The levels of serum nitric oxide, endogenous nitric oxide synthase and nitric oxide/endothelin-1 after exercise in the aerobic exercise group and the combined exercise group were all higher than those before exercise (P < 0.05). These findings indicate that both 8-week aerobic exercise and aerobic exercise combined with full-body vibration training can improve the microcirculation function of obese subjects, and the intervention effect of aerobic exercise combined with full-body vibration training is better. Promoting endogenous nitric oxide release and increasing nitric oxide/endothelin-1 levels may be the potential mechanism by which exercise improves microcirculation function.

Key words: obesity, aerobic exercise, full-body vibration training, microcirculation function, nitric oxide, endothelin 1, endogenous nitric oxide synthase