Wasserman D H, Whipp B J
J Appl Physiol Respir Environ Exerc Physiol. 1983 Feb;54(2):587-93. doi: 10.1152/jappl.1983.54.2.587.
During steady-state exercise, ventilation increases in proportion to CO2 output (VCO2), regulating arterial PCO2. To characterize the dynamics of ventilatory coupling to VCO2 and O2 uptake (VO2) in the nonsteady-state phase, seven normal subjects performed constant-load cycle ergometry to a series of subanaerobic threshold work rates. Each bout consisted of eight 6-min periods of alternating loaded and unloaded cycling. Ventilation and gas exchange variables were computed breath by breath, with the time-averaged response dynamics being established off-line. Ventilation increased as a linear function of VCO2 in all cases, the relationship being identical in the steady- and the nonsteady-state phases. Ventilation, however, bore a curvilinear relation to VO2, the kinetics of the latter being more rapid. Owing to the kinetic disparity between expired minute ventilation (VE) and VO2, there was an overshoot in the direction of change in VE/VO2 and end-tidal PO2 during the work-rate transition. In contrast, there was no overshoot in the direction of change in VE/VCO2 and end-tidal PCO2 throughout the nonsteady-state period. These data suggest that the exercise hyperpnea is coupled to metabolism in men via a signal proportional to VCO2 in both the nonsteady and steady states of moderate exercise.
在稳态运动期间，通气量与二氧化碳排出量（VCO2）成比例增加，从而调节动脉血二氧化碳分压（PCO2）。为了描述非稳态阶段通气与VCO2和氧气摄取量（VO2）耦合的动态变化，七名正常受试者在一系列低于无氧阈的工作强度下进行了恒定负荷的自行车测力计运动。每次运动由八个6分钟的交替加载和卸载骑行周期组成。逐次计算通气量和气体交换变量，并离线建立时间平均响应动态。在所有情况下，通气量均作为VCO2的线性函数增加，稳态和非稳态阶段的关系相同。然而，通气量与VO2呈曲线关系，后者的动力学变化更快。由于呼出分钟通气量（VE）和VO2之间的动力学差异，在工作强度转换期间，VE/VO2和呼气末氧分压（PO2）的变化方向出现了过冲。相比之下，在整个非稳态期间，VE/VCO2和呼气末二氧化碳分压（PCO2）的变化方向没有过冲。这些数据表明，在中等强度运动的非稳态和稳态阶段，运动性通气过度均通过与VCO2成比例的信号与男性的代谢相耦合。
