Objective: The purpose of this study was to investigate the effects of 4-week HiHiLo training on the injury and recovery of myocardial in obese people. Methods: 12 men with over more than 25% body fat and 12 women with more than 30% body fat were recruited, and then divided into hypoxic (HiHiLo) or normoxic (NOR) group randomly and equally. Hypoxic group stayed 9 hours every night in hypoxic chamber where oxygen content of 16%(simulate altitude of 2200m) at the beginning, then the oxygen content dropped to 14%(simulate altitude of 3300m) gradually within 4 weeks. They were required to be normoxicly trained with the intensity of individual 80% HRmax for 2 hours per day, 6 to 7 days a week. Apart from the same normoxic training loads for 4 to 5 days as normoxic group, hypoxic group were additionally trained under hypoxic circumstance (the oxygen content was 15.5%, simulate altitude of 2500m) for 1.5 hours per day, 2 days a week. Training methods included aerobics, power cycling, running, dumbbell gymnastics and vibration training. The conditions of the normoxic group were fully consistent with hypoxic group, but living and training in normoxic environment. Venous blood samples were collected at the day before experiment, after 9 hours of acute hypoxic exposure and the second and the fourth weekend. The levels of serum CK, CK-MB, cTnI, were measured. Results: After 9 hours of acute hypoxic exposure, the oxygen content of 16%(simulate altitude of 2200m), the level of Heart Rate, CK and CK-MB/CK increased significantly. 4-week HiHiLo training caused the levels of CK and cTnI increased first and then decreased significantly while normoxic group had no changes in CK and cTnI. Conclusion: The level of CK and CK-MB/CK increased significantly after 9h acute hypoxic exposure. It suggest that CK and CK-MB/CK may be the sensitive iv indicators of myocardial injury under acute hypoxic exposure. HiHiLo is beneficial to myocardial damnificantion recover from the high-intensity training. No significantly additional hypoxia effect could be concluded insufficient simulate altitude and short sojourn duration.

研究目的：研究旨在探討高住高訓低練對肥胖者心肌損傷及恢復的影響。 研究方法：本研究採用組內組間設計的準實驗法實施。實驗對象為身體脂肪含量 高於25%或BMI>25的男性及身體脂肪含量高於30%或BMI>25的女性各12名，將 其隨機分為低氧組與常氧組，兩組中男女受試者各6名。低氧組進行為期4週的高 住高訓低練（HiHiLo）：住宿採用常壓低氧房，4週內房內氧濃度由16%（相當於 海拔2200m）逐漸降至14%（相當於海拔3300m），每晚低氧住宿9小時；每週常 氧訓練4～5天，每天訓練2小時；每週低氧（15.5%氧濃度，相當於海拔2500m） 訓練2天，每天1.5小時。訓練方式為健美操、蹬功率自行車、跑步、啞鈴操及振 動訓練交替進行，強度大約為個體80%HRmax。常氧組除居住在常氧環境及每週6 ～7天均為常氧訓練外，其他條件與低氧組完全一致。分別於實驗前1天、急性低 氧暴露9小時、實驗第2、4週末採集清晨空腹靜脈血，分離血清測定肌酸激酶 （CK）、肌酸激酶MB同工酶（CK-MB）、心肌鈣蛋白I（cTnI）水準。 研究結果：1）9小時模擬海拔2200米（氧濃度為16.07%）急性低氧暴露後，心率、 CK、CK-MB/CK比值顯著升高。2）為期4週的高住高訓低練引起CK、cTnI水準 先升高，後顯著降低，而常氧訓練結果不明顯。 結論:9h的急性低氧暴露後CK、CK-MB/CK值顯著升高，提示該指標可能是急性 低氧暴露下，反應心肌損傷的敏感指標；HiHiLo的運動方式能使大強度訓練後引 起的心肌損傷得到一定的恢復；組間效應無統計學上的顯著差異可能與模擬高度 較低及實驗週期較短有關。