Koppo K, Bouckaert J
Department of Movement and Sports Sciences, University of Ghent, Belgium.
Eur J Appl Physiol. 2000 Dec;83(6):559-65. doi: 10.1007/s004210000295.
The aim of the study was to examine to what extent prior high- or low-intensity cycling, yielding the same amount of external work, influenced the oxygen uptake (VO2) slow component of subsequent high-intensity cycling. The 12 subjects cycled in two protocols consisting of an initial 3 min period of unloaded cycling followed by two periods of constant-load exercise separated by 3 min of rest and 3 min of unloaded cycling. In protocol 1 both periods of exercise consisted of 6 min cycling at a work rate corresponding to 90% peak oxygen uptake (VO2peak). Protocol 2 differed from protocol 1 in that the first period of exercise consisted of a mean of 12.1 (SD 0.8) min cycling at a work rate corresponding to 50% VO2peak. The difference between the 3rd min VO2 and the end VO2 (deltaVO2(6-3)) was used as an index of the VO2 slow component. Prior high-intensity exercise significantly reduced deltaVO2(6-3). The deltaVO2(6-3) was also reduced by prior low-intensity exercise despite an unchanged plasma lactate concentration at the start of the second period of exercise. The reduction was more pronounced after prior high- than after prior low-intensity exercise (59% and 28%, respectively). The results of this study show that prior exercise of high as well as low intensity reduces the VO2 slow component and indicate that a metabolic acidosis is not a necessary condition to elicit a reduction in deltaVO2(6-3).
本研究的目的是探讨在产生相同量的外部功的情况下，先前的高强度或低强度骑行在多大程度上影响随后高强度骑行的摄氧量（VO2）慢成分。12名受试者按照两种方案进行骑行，每种方案包括最初3分钟的无负荷骑行，随后是两个恒定负荷运动阶段，中间间隔3分钟休息和3分钟无负荷骑行。在方案1中，两个运动阶段均为以对应于90%峰值摄氧量（VO2peak）的工作强度进行6分钟骑行。方案2与方案1的不同之处在于，第一个运动阶段为以对应于50%VO2peak的工作强度平均骑行12.1（标准差0.8）分钟。第3分钟VO2与运动结束时VO2的差值（deltaVO2(6 - 3)）用作VO2慢成分的指标。先前的高强度运动显著降低了deltaVO2(6 - 3)。尽管在第二个运动阶段开始时血浆乳酸浓度未变，但先前的低强度运动也降低了deltaVO2(6 - 3)。与先前低强度运动相比，先前高强度运动后的降低更为明显（分别为59%和28%）。本研究结果表明，先前的高强度和低强度运动均会降低VO2慢成分，并表明代谢性酸中毒并非引发deltaVO2(6 - 3)降低的必要条件。
