Mucci P, Prioux J, Hayot M, Ramonatxo M, Préfaut C
Laboratoire de Physiologie des Interactions, Hôpital Arnaud de Villeneuve, Montpellier, France.
Eur J Appl Physiol Occup Physiol. 1998 Mar;77(4):343-51. doi: 10.1007/s004210050343.
Exercise-induced hypoxaemia (EIH) in master athletes may be related to a diminished exercise hyperpnoea. The aim of this study was to determine whether EIH is associated with a change in the sensitivity of the ventilation response to activation of the central chemoreceptors. The ventilation response to CO2 was measured in nine elderly untrained men (UT) [mean age 66.3 (SEM 3.1) years] and nine master athletes (MA) [mean age 62.7 (SEM 0.8) years] at rest, during moderate exercise (40% maximal oxygen uptake, VO2max), and during strenuous exercise (70% VO2max) using the rebreathing method. Our results showed that the ventilation response to CO2 did not differ with endurance training and/or exercise, that the threshold of the CO2 response (Th) increased with exercise (P < 0.001), that the increase in Th in MA was higher than in UT between rest and moderate exercise [deltaTh(0-40): 8.55 (SEM 1.8) vs 3.06 (SEM 1.72) mmHg, P < 0.05], and that deltaTh(0-40) and Th during moderate exercise were negatively correlated with arterial O2 saturation during maximal exercise (r=0.50, P<O0.05). We concluded therefore that exercise-induced hypoxaemia in master athletes may not be due to a lower ventilation response to CO2, but may be partly related to a greater increase in Th during moderate exercise.
优秀运动员的运动诱发低氧血症（EIH）可能与运动性通气过度减弱有关。本研究的目的是确定EIH是否与中枢化学感受器激活时通气反应敏感性的变化有关。采用重复呼吸法，在9名未经训练的老年男性（UT）[平均年龄66.3（标准误3.1）岁]和9名优秀运动员（MA）[平均年龄62.7（标准误0.8）岁]休息时、中等强度运动（最大摄氧量的40%，VO2max）期间和剧烈运动（VO2max的70%）期间测量了对二氧化碳的通气反应。我们的结果表明，对二氧化碳的通气反应在耐力训练和/或运动时没有差异，二氧化碳反应阈值（Th）随运动增加（P<0.001），在休息至中等强度运动期间，MA的Th增加高于UT[δTh(0-40)：8.55（标准误1.8）与3.06（标准误1.72）mmHg，P<0.05]，并且中等强度运动时的δTh(0-40)和Th与最大运动时的动脉血氧饱和度呈负相关（r=0.50，P<0.05）。因此，我们得出结论，优秀运动员的运动诱发低氧血症可能不是由于对二氧化碳的通气反应较低，而是可能部分与中等强度运动期间Th的更大增加有关。
