Maximal Aerobic Capacity at Several Ambient Concentrations of Carbon Monoxide at Several Altitudes

摘要

To assess the combined effects of altitude and acute carbon monoxide exposure, 11 male and 12 female subjects, all nonsmokers in good health, were given incremental maximal aerobic capacity tests. Each subject, after attaining the required altitude and ambient carbon monoxide level, performed the maximal aerobic capacity test. Blood samples were drawn at several points in the aerobic capacity test protocol, and analyzed for hemoglobin, hematocrit, plasma proteins, lactates, and carboxyhemoglobin. Carbon-monoxide-carboxyhemoglobin uptake rates were derived from the submaximal workloads. Despite increases in carboxyhemoglobin, no additional significant decreases in maximal aerobic capacity were observed. Immediately prior to and at maximal workloads, carbon monoxide shifted into extravascular spaces and returned to the vascular space within five minutes after exercise stopped.