Vella Chantal A, Marks Derek, Robergs Robert A
Exercise Physiology Laboratories, The University of Texas at El Paso, TX 79902, USA.
Respirology. 2006 Mar;11(2):175-81. doi: 10.1111/j.1440-1843.2006.00825.x.
Evidence of significant oxygen requirements for ventilation during exercise (exercise hyperpnoea) prompted the investigation into whether the oxygen cost of ventilation affects the presence of a whole-body VO(2) plateau at maximal exercise. The purposes of this study were to: (i) use isocapnic hyperpnoea trials to determine the oxygen cost of ventilation (VO(2VENT)) across a range of ventilation (V(E)); (ii) determine the mean VO(2VENT) at maximal exercise expressed as a percentage of whole-body VO(2) max; and (iii) determine if a plateau in VO(2) is more evident when the VO(2VENT) is subtracted from whole-body VO(2) at maximal exercise.
A total of 21 subjects performed a VO(2) max test on the cycle ergometer to determine the range of V(E) for each subject. From the initial VO(2) max test, nine V(E) values across the range of V(E) were selected for each subject and the oxygen cost of each was measured.
The mean maximal VO(2VENT) equalled 8.8 +/- 3.3% of VO(2) max and ranged from 5.0% to 17.6%. VO(2VENT) increased exponentially with increasing V(E), but there was considerable subject variability in the oxygen cost per litre of V(E) as V(E) increased. Subtracting the VO(2VENT) from whole-body VO(2) at maximal exercise increased the detection of a plateau in VO(2) at VO(2) max.
The data of the present study indicate that the VO(2VENT) is a significant portion of VO(2) max and may be a limiting factor of maximal exercise performance in some subjects.
运动期间通气对氧气有显著需求（运动性通气过度）的证据促使人们研究通气的氧耗是否会影响最大运动时全身耗氧量（VO₂）平台的出现。本研究的目的是：（i）通过等碳酸通气试验确定一系列通气量（V̇E）下的通气氧耗（VO₂VENT）；（ii）确定最大运动时平均VO₂VENT占全身最大摄氧量（VO₂max）的百分比；（iii）确定在最大运动时从全身VO₂中减去VO₂VENT后，VO₂平台是否更明显。
共有21名受试者在功率自行车上进行了VO₂max测试，以确定每个受试者的V̇E范围。从最初的VO₂max测试中，为每个受试者在V̇E范围内选择9个V̇E值，并测量每个值的氧耗。
平均最大VO₂VENT等于VO₂max的8.8±3.3%，范围为5.0%至17.6%。VO₂VENT随V̇E增加呈指数增加，但随着V̇E增加，每升V̇E的氧耗存在相当大的个体差异。在最大运动时从全身VO₂中减去VO₂VENT增加了在VO₂max时VO₂平台的检测率。
本研究数据表明，VO₂VENT是VO₂max的重要组成部分，可能是一些受试者最大运动表现的限制因素。
