Day J R, Rossiter H B, Coats E M, Skasick A, Whipp B J
Department of Physiology, St. George's Hospital Medical School, London, United Kingdom.
J Appl Physiol (1985). 2003 Nov;95(5):1901-7. doi: 10.1152/japplphysiol.00024.2003. Epub 2003 Jul 11.
The quantification of maximum oxygen uptake (V(O2 max)), a parameter characterizing the effective integration of the neural, cardiopulmonary, and metabolic systems, requires oxygen uptake (VO2) to attain a plateau. We were interested in whether a VO2 plateau was consistently manifest during maximal incremental ramp cycle ergometry and also in ascertaining the relationship between this peak VO2 (V(O2 peak)) and that determined from one, or several, maximal constant-load tests. Ventilatory and pulmonary gas-exchange variables were measured breath by breath with a turbine and mass spectrometer. On average, V(O2 peak) [3.51 +/- 0.8 (SD) l/min] for the ramp test did not differ from that extrapolated from the linear phase of the response in 71 subjects. In 12 of these subjects, the V(O2 peak) was less than the extrapolated value by 0.1-0.4 l/min (i.e., a "plateau"), and in 19 subjects, V(O2 peak) was higher by 0.05-0.4 l/min. In the remaining 40 subjects, we could not discriminate a difference. The V(O2 peak) from the incremental test also did not differ from that of a single maximum constant-load test in 38 subjects or from the V(O2 max) in 6 subjects who undertook a range of progressively greater discontinuous constant-load tests. A plateau in the actual VO2 response is therefore not an obligatory consequence of incremental exercise. Because the peak value attained was not different from the plateau in the plot of VO2 vs. work rate (for the constant-load tests), the V(O2 peak) attained on a maximum-effort incremental test is likely to be a valid index of V(O2 max), despite no evidence of a plateau in the data themselves. However, without additional tests, one cannot be certain.
最大摄氧量（V（O2 max））是表征神经、心肺和代谢系统有效整合的一个参数，对其进行量化需要摄氧量（VO2）达到平稳状态。我们感兴趣的是，在最大递增斜坡式周期功率计测试过程中，VO2平稳状态是否始终会出现，同时也想确定这个峰值VO2（V（O2 peak））与通过一次或几次最大恒定负荷测试所确定的VO2之间的关系。使用涡轮机和质谱仪逐次测量通气和肺气体交换变量。斜坡测试的V（O2 peak）平均为[3.51±0.8（标准差）升/分钟]，与71名受试者响应线性阶段外推得出的值无差异。在这些受试者中，有12名的V（O2 peak）比外推值低0.1 - 0.4升/分钟（即出现“平稳状态”），19名受试者的V（O2 peak）比外推值高0.05 - 0.4升/分钟。在其余40名受试者中，我们无法区分差异。递增测试的V（O2 peak）与38名受试者单次最大恒定负荷测试的V（O2 peak）或6名进行一系列逐步增加的不连续恒定负荷测试的受试者的V（O2 max）也无差异。因此，实际VO2响应中的平稳状态并非递增运动的必然结果。由于达到的峰值与VO2对工作率的曲线中的平稳状态无差异（对于恒定负荷测试），尽管数据本身没有平稳状态的证据，但在最大努力递增测试中达到的V（O2 peak）可能是V（O2 max）的有效指标。然而，没有额外测试，无法确定。
