Abstract：
This study investigates whether exercise as a strategy for improving physical fitness at sea level also offers comparable benefits in the unique context of high altitudes (HA), considering the physiological challenges of hypoxic conditions. Overall, 121 lowlanders who had lived on the Tibetan Plateau for >2 years and were still living at HA during the measurements were randomly classified into four groups. Each individual of the low-intensity (LI), moderate-intensity (MI), and high-intensity (HI) groups performed 20 sessions of aerobic exercise at HA (3680 m) over 4 weeks, while the control group (CG) did not undergo any intervention. Physiological responses before and after the intervention were observed. The LI and MI groups experienced significant improvement in cardiopulmonary fitness (0.27 and 0.35 L/min increases in peak oxygen uptake [ V ˙ $\\dot{\\mathrm{V}}$ O2peak], both p < 0.05) after exercise intervention, while the hematocrit (HCT) remained unchanged (p > 0.05). However, HI exercise was less efficient for cardiopulmonary fitness of lowlanders (0.02 L/min decrease in V ˙ $\\dot{\\mathrm{V}}$ O2peak, p > 0.05), whereas both the HCT (1.74 %, p < 0.001) and glomerular filtration rate (18.41 mL/min, p < 0.001) increased with HI intervention. Therefore, LI and MI aerobic exercise, rather than HI, can help lowlanders in Tibet become more acclimated to the HA by increasing cardiopulmonary function and counteracting erythrocytosis.
摘要：
这项研究调查了运动作为改善海平面身体素质的策略是否在高海拔（HA）的独特背景下也提供了可比的好处，考虑到低氧条件的生理挑战。总的来说,将121名在青藏高原生活>2年并且在测量期间仍生活在HA的低地居民随机分为四组。每个低强度的个体（LI），中等强度(MI)，和高强度（HI）组进行了20次有氧运动在HA（3680米）超过4周，对照组（CG）未进行任何干预。观察干预前后的生理反应。LI和MI组的心肺适应性得到了显着改善（峰值摄氧量增加0.27和0.35L/min[V•$\\dot{\\mathrm{V}}$O2peak]，两者p<0.05)运动干预后，而血细胞比容（HCT）保持不变（p>0.05）。然而,HI锻炼对低地人的心肺健康效率较低(V·$\\dot{\\mathrm{V}}$O2peak,P>0.05)，而两者的HCT(1.74%，p<0.001）和肾小球滤过率（18.41mL/min，p<0.001）随HI干预而增加。因此,LI和MI有氧运动，而不是HI，可以通过增加心肺功能和抵抗红细胞增多来帮助西藏的低地居民更加适应HA。
