Katayama K, Sato Y, Ishida K, Mori S, Miyamura M
Research Center of Health, Physical Fitness and Sports, Nagoya University, Japan.
Eur J Appl Physiol Occup Physiol. 1998 Aug;78(3):189-94. doi: 10.1007/s004210050406.
The present study was performed to investigate the effects of a combination of intermittent exposure to hypoxia during exercise training for short periods on ventilatory responses to hypoxia and hypercapnia (HVR and HCVR respectively) in humans. In a hypobaric chamber at a simulated altitude of 4,500 m (barometric pressure 432 mmHg), seven subjects (training group) performed exercise training for 6 consecutive days (30 min x day(-1)), while six subjects (control group) were inactive during the same period. The HVR, HCVR and maximal oxygen uptake (VO2max) for each subject were measured at sea level before (pre) and after exposure to intermittent hypoxia. The post exposure test was carried out twice, i.e. on the 1st day and 1 week post exposure. It was found that HVR, as an index of peripheral chemosensitivity to hypoxia, was increased significantly (P < 0.05) in the control group after intermittent exposure to hypoxia. In contrast, there was no significant increase in HVR in the training group after exposure. The HCVR in both groups was not changed by intermittent exposure to hypoxia, while VO2max increased significantly in the training group. These results would suggest that endurance training during intermittent exposure to hypoxia depresses the increment of chemosensitivity to hypoxia, and that intermittent exposure to hypoxia in the presence or absence of exercise training does not induce an increase in the chemosensitivity to hypercapnia in humans.
本研究旨在探讨在运动训练期间短时间间歇性低氧暴露的联合作用对人体低氧和高碳酸血症通气反应（分别为HVR和HCVR）的影响。在模拟海拔4500米（气压432 mmHg）的低压舱中，7名受试者（训练组）连续6天进行运动训练（每天30分钟），而6名受试者（对照组）在同一时期不进行活动。在海平面上，在间歇性低氧暴露之前（预）和之后测量每个受试者的HVR、HCVR和最大摄氧量（VO2max）。暴露后测试进行两次，即在暴露后的第1天和1周。结果发现，作为外周对低氧化学敏感性指标的HVR，在对照组间歇性低氧暴露后显著增加（P < 0.05）。相反，训练组暴露后HVR没有显著增加。两组的HCVR在间歇性低氧暴露后没有变化，而训练组的VO2max显著增加。这些结果表明，间歇性低氧暴露期间的耐力训练会抑制对低氧化学敏感性的增加，并且无论是否进行运动训练，间歇性低氧暴露都不会导致人体对高碳酸血症化学敏感性的增加。
