Eight-week aerobic exercise and aerobic exercise combined with full-body vibration training improve the microcirculation function of obese college students

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 a matched grouping method: control group (n=20) did not undergo systematic exercise training; aerobic exercise group (n=20) performed 8 weeks of aerobic jogging (4 times per week, 60 min each); combined exercise group (n=20) performed 8 weeks of aerobic exercise combined with full-body vibration training [4 times per week, 60 min each (51 min aerobic jogging + 9 min full-body vibration training)]. Before and after the exercise intervention, microvascular reactivity, transcutaneous oxygen pressure, muscle oxygen saturation, and serum levels of nitric oxide, endothelial nitric oxide synthase, and endothelin-1 were measured in all three groups. RESULTS AND CONCLUSION: (1) After the intervention, the heated values of microvascular blood perfusion, blood cell concentration, blood cell velocity, transcutaneous oxygen pressure, and muscle oxygen saturation in the aerobic exercise and combined exercise groups were higher than those in the control group (P < 0.05). The combined exercise group showed higher values than the aerobic exercise group (P < 0.05). In the combined exercise group, the baseline values of microvascular blood perfusion and blood cell velocity after intervention were higher than before (P < 0.01). In both exercise groups, the heated values of microvascular blood perfusion, blood cell concentration, blood cell velocity, transcutaneous oxygen pressure, and muscle oxygen saturation were higher after intervention than before (P < 0.05, P < 0.01). (2) After the intervention, serum levels of nitric oxide, endothelial nitric oxide synthase, and nitric oxide/endothelin-1 ratio in the aerobic exercise and combined exercise groups were higher than those in the control group (P < 0.05), while serum endothelin-1 levels were lower (P < 0.05). The combined exercise group had higher nitric oxide, endothelial nitric oxide synthase, and nitric oxide/endothelin-1 ratio than the aerobic exercise group (P < 0.05), and lower endothelin-1 levels (P < 0.05). In both exercise groups, serum nitric oxide, endothelial nitric oxide synthase, and nitric oxide/endothelin-1 ratio increased after intervention (P < 0.05, P < 0.01), while endothelin-1 decreased (P < 0.01). (3) These results indicate that 8 weeks of aerobic exercise and aerobic exercise combined with full-body vibration training can improve microcirculation function in obese subjects, with the combined intervention being more effective. Promoting endogenous nitric oxide release and increasing the nitric oxide/endothelin-1 ratio may be the potential mechanism by which exercise improves microcirculation function.

1. Introduction

Obesity is a chronic disease characterized by fat accumulation and metabolic disorders, and it is a major public health problem worldwide [1-3]. Microcirculation refers to the blood circulation between arterioles and venules, typically consisting of seven parts: arterioles, metarterioles, precapillary sphincters, true capillaries, thoroughfare channels, arteriovenous anastomoses, and venules. Its core function is to facilitate material exchange between blood and tissues/cells. Microcirculation dysfunction plays an important role in the occurrence and development of obesity, with decreased microvascular reactivity and microvascular rarefaction being the main manifestations and early events in obese individuals [4-5]. Microcirculation dysfunction not only increases the risk of ischemic heart disease, type 2 diabetes, and hypertension, but also impairs material exchange efficiency in tissues such as skeletal muscle, reducing exercise tolerance [6-7]. As obesity severity increases, microcirculation dysfunction further worsens [8]. Therefore, improving microcirculation dysfunction in obese individuals is crucial not only for reducing chronic disease risk but also for enhancing exercise capacity and physical activity levels, thereby promoting weight loss and fat reduction.

Aerobic exercise is an effective way to improve microcirculation function in obese individuals through multiple pathways [4,6,9]. For instance, TANG et al. [10] found that 6 weeks of aerobic exercise combined with dietary intervention effectively reduced waist circumference and improved glucose and lipid metabolism and microvascular reactive hyperemia in obese adolescents. Additionally, 8 weeks of moderate-intensity aerobic exercise improved skin microvascular reactivity and plasma adiponectin levels in obese subjects [11], and 8 weeks of aerobic exercise also increased microvascular blood flow and muscle oxygen saturation in obese subjects [12]. These studies collectively suggest that aerobic exercise significantly improves microcirculation function in obese populations, providing evidence from various aspects of microcirculation assessment.

Furthermore, as an emerging exercise modality, full-body vibration training has also been shown to improve microcirculation function. However, most existing studies have focused on single exercise forms, and research on the combined effects of aerobic exercise and full-body vibration training is limited. Therefore, this study aimed to compare the effects of 8 weeks of aerobic exercise alone versus aerobic exercise combined with full-body vibration training on microcirculation function in obese college students, and to explore the potential underlying mechanisms.