Hughson R L
Department of Kinesiology, University of Waterloo, Ontario, Canada.
Med Sci Sports Exerc. 1990 Feb;22(1):72-9.
The rate of increase in oxygen uptake (VO2) at the onset of a step change in work rate can be studied to provide information about the physiological mechanisms that control this process. Several systems must interact to produce the total response. These can be grouped into oxygen transport and oxygen utilization mechanisms. In this paper, the hypothesis that one or the other of these mechanisms limits the adaptation of VO2 to a change in work rate will be examined. In addition to the traditional approach with step changes in work rate, the responses to other work rate forcing functions will be reported. These include ramp, impulse, and pseudorandom binary sequence work rate changes. The evidence that is accumulating from studies involving transitions from different baseline levels of exercise, as well as studies of the effects of hypoxia and beta-adrenergic receptor blockade, has led to the conclusion that oxygen transport mechanisms limit the rate of increase in VO2. However, the dynamic response of VO2 in the presence of adequate oxygen is not much different from that of oxygen limited conditions.
在工作负荷发生阶跃变化开始时，氧气摄取量（VO2）的增加速率可用于研究，以提供有关控制该过程的生理机制的信息。几个系统必须相互作用才能产生整体反应。这些可分为氧气运输和氧气利用机制。在本文中，将检验这些机制中的一种或另一种限制VO2适应工作负荷变化的假说。除了采用工作负荷阶跃变化的传统方法外，还将报告对其他工作负荷强迫函数的反应。这些包括斜坡、脉冲和伪随机二进制序列工作负荷变化。来自涉及从不同运动基线水平转变的研究以及缺氧和β-肾上腺素能受体阻断作用研究积累的证据得出结论，氧气运输机制限制了VO2的增加速率。然而，在有充足氧气的情况下VO2的动态反应与氧气受限条件下的动态反应没有太大差异。
