PDF(Pubmed)
Abstract：
This study explores the effects of normobaric hypoxia and intermittent hypoxic training (IHT) on the physiological condition of the cardiac muscle in swimmers. Hypoxia has been reported to elicit both beneficial and adverse changes in the cardiovascular system, but its impact on the myocardium during acute exercise and altitude/hypoxic training remains less understood. We aimed to determine how a single bout of intense interval exercise and a four-week period of high-intensity endurance training under normobaric hypoxia affect cardiac marker activity in swimmers. Sixteen young male swimmers were divided into two groups: one undergoing training in hypoxia and the other in normoxia. Cardiac markers, including troponin I and T (cTnI and cTnT), heart-type fatty acid-binding protein (H-FABP), creatine kinase-MB isoenzyme (CK-MB), and myoglobin (Mb), were analyzed to assess the myocardium\'s response. We found no significant differences in the physiological response of the cardiac muscle to intense physical exertion between hypoxia and normoxia. Four weeks of IHT did not alter the resting levels of cTnT, cTnI, and H-FABP, but it resulted in a noteworthy decrease in the resting concentration of CK-MB, suggesting enhanced cardiac muscle adaptation to exercise. In contrast, a reduction in resting Mb levels was observed in the control group training in normoxia. These findings suggest that IHT at moderate altitudes does not adversely affect cardiac muscle condition and may support cardiac muscle adaptation, affirming the safety and efficacy of IHT as a training method for athletes.
摘要：
本研究探讨了常压低氧和间歇性低氧训练（IHT）对游泳者心肌生理状况的影响。据报道，缺氧会引起心血管系统的有益和不利变化，但其在急性运动和高原/低氧训练期间对心肌的影响尚不清楚。我们旨在确定在常压低氧条件下进行一次激烈的间歇运动和为期四周的高强度耐力训练如何影响游泳者的心脏标志物活性。16名年轻男子游泳运动员分为两组：一组在缺氧条件下进行训练，另一组在常氧条件下进行训练。心脏标志物,包括肌钙蛋白I和T（cTnI和cTnT），心型脂肪酸结合蛋白(H-FABP),肌酸激酶-MB同工酶（CK-MB），和肌红蛋白（Mb），进行分析以评估心肌反应。我们发现在缺氧和常氧之间，心肌对剧烈体力消耗的生理反应没有显着差异。四周的IHT没有改变cTnT的静息水平，cTnI,和H-FABP,但它导致CK-MB的静息浓度显着下降，提示心肌对运动的适应性增强。相比之下,对照组在常氧训练中观察到静息Mb水平降低。这些发现表明，在中等海拔高度的IHT不会对心肌状况产生不利影响，并可能支持心肌适应。肯定IHT作为运动员训练方法的安全性和有效性。
