Leyk D, Essfeld D, Hoffmann U, Baum K, Stegemann J
Physiologisches Institut der Deutschen Sporthochschule Köln, Federal Republic of Germany.
Eur J Appl Physiol Occup Physiol. 1992;65(6):499-506. doi: 10.1007/BF00602355.
Parallel measurements of breath-by-breath oxygen uptake, cardiac output (Doppler technique), blood pressure (Finapres technique) and heart rate were performed in nine subjects during cycle ergometer exercise in the upright and supine positions. Transients were monitored during power steps starting from and leading to either rest or lower levels of exercise intensity. Oxygen uptake (VO2) and cardiac output kinetics were markedly faster than in all other conditions when exercise was started from rest. In contrast to exercise-exercise on steps, the computed arteriovenous difference in O2 content increased almost immediately in this situation, indicating that not only the additional energy expenditure due to the acceleration of the flywheel but also an increased venous admixture from non-exercising parts of the body contributed to the early kinetics. The off kinetics generally showed a more uniform pattern and did not simply mirror the on transients. The present findings indicate that transitions from rest should be avoided when muscle VO2 kinetics are to be assessed on the basis of VO2 measurements at the mouth.
在9名受试者进行卧式和立式自行车测力计运动期间，逐次测量摄氧量、心输出量（多普勒技术）、血压（Finapres技术）和心率。在从休息或较低运动强度开始并导致功率变化的过程中监测瞬态变化。当运动从休息开始时，摄氧量（VO2）和心输出量动力学明显快于所有其他情况。与阶梯上的运动-运动情况相反，在这种情况下，计算得出的动静脉氧含量差异几乎立即增加，这表明不仅飞轮加速导致额外的能量消耗，而且身体非运动部位静脉混合增加也促成了早期动力学。运动结束时的动力学通常表现出更均匀的模式，并非简单地反映运动开始时的瞬态变化。目前的研究结果表明，当要根据口腔处的VO2测量来评估肌肉VO2动力学时，应避免从休息状态开始转换。
