Aquatic exercise in hypobaric hypoxic environment for the lifestyle-related disease improvement

本研究旨在建立一种改善生活方式相关疾病的有益运动疗法，确定低压低氧环境下水上运动对心血管反应、葡萄糖和脂肪代谢的影响。健康的3个青壮年组A （n=6）、B （n=6）、C （n=6）和中年组D （n=5）进行约50%VO2max强度的水中运动，每次30分钟，持续4周。A、B、D分别暴露在海拔2000米对应的缺氧条件下，C暴露在海拔2500米对应的缺氧条件下，时间为2.5小时/次。A组训练频率为4次/周，B、C、d组训练频率为3次/周。训练前后测量VO_2max和训练前测定的50%VO_2max强度下自行车运动时的心率（HR）、脑卒中量（SV）、心输出量（CO）、收缩压（SBP）、舒张压（DBP）、平均血压（MBP）等心血管反应。训练4周后，各组VO_2max均无明显变化。在适度运动期间的心血管反应中，B和d没有明显变化，而A和C的SV和CO明显增加。口服糖耐量试验后，曲线下面积和120 min血胰岛素浓度仅在C组显著降低。血脂中，a、B组总胆固醇和LDL显著降低，C、d组无显著降低。a、B、C组皮褶厚度显著降低，d组无显著降低。我们的研究结果表明，在低气压低氧环境下进行水上运动可以更有效地诱导心血管功能、葡萄糖和脂肪代谢的有益变化。这些新发现为利用低氧运动预防和临床治疗生活方式相关疾病提供了积极的可能性。

Present study aimed to establish a beneficial exercise therapy for lifestyle-related disease improvement, determining the effects of aquatic exercise in hypobaric hypoxic environment gives on cardiovascular response, glucose and fat metabolism.Healthy 3 young adult groups, A (n=6), B (n=6), C (n=6), and middle-aged group D (n=5) performed an aquatic exercise at the intensity of around 50%VO2max for 30 min/session, for 4 weeks. A, B and D were exposed to hypoxic condition corresponding to 2000m and C was exposed to 2500m above sea level for 2.5hours/session. The training frequency was 4 times/week in A and 3 times/week in B, C and D. Before and after the training period, VO_2max and cardiovascular responses such as heart rate (HR), stroke volume (SV), cardiac output (CO), and systolic (SBP), diastolic (DBP) and mean blood pressure (MBP) during cycling exercise at the intensity of 50%VO_2max, which was determined before the training, were measured.After the 4 weeks of training, VO_2max did not change significantly in all groups. In cardiovascular responses during the moderate exercise, no significant changes were observed in B and D. On the other hand, SV and CO in A and C significantly increased. In addition, a significant decrease was observed in DBP and MBP in A and C. Also, after the oral glucose tolerance test, under-curve area and blood insulin concentration by 120 min were significantly reduced only in C. In blood lipid, total cholesterol and LDL were significantly decreased in A and B, but not in C and D. A significant decrease was observed in skinfold thickness in A, B and C, but not D. Taken all, our results revealed that an aquatic exercise in hypobaric hypoxic environment would induce more effectively the beneficial changes in cardiovascular function, glucose and fat metabolism. These new findings would open the positive possibilities of utilizing hypoxia with exercise for prevention and clinical treatment of lifestyle-related disease.