Spina Robert J, Meyer Timothy E, Peterson Linda R, Villareal Dennis T, Rinder Morton R, Ehsani Ali A
Section of Applied Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
J Appl Physiol (1985). 2004 Nov;97(5):1654-9. doi: 10.1152/japplphysiol.01303.2003.
Recent evidence suggests that octogenarians exhibit attenuated adaptations to training with a small increase in peak O2 consumption (VO2) that is mediated by a modest improvement in cardiac output without an increase in arteriovenous O2 content difference. This study was designed to determine whether diminished increases in peak VO2 and cardiac output in the octogenarians are associated with absence of left ventricular and arterial adaptations to exercise training. We studied 22 octogenarians (81.9 +/- 3.7 yr, mean +/- SD) randomly assigned a group that exercised at an intensity of 82.5 +/- 5% of peak heart rate for 9 mo and 14 (age 83.1 +/- 4.1) assigned to a control group. Peak VO2 increased 12% in the exercise group but decreased slightly (-7%) in the controls. The exercise group demonstrated significant but small decreases in the heart rate (6%, P = 0.002) and the rate-pressure product (9%, P = 0.004) during submaximal exercise at an absolute work rate. Training induced no significant changes in the left ventricular size, geometry (wall thickness-to-radius ratio), mass, and function assessed with two-dimensional echocardiography or in arterial stiffness evaluated with applanation tonometry. Data suggest that the absence of cardiac and arterial adaptations may in part account for the limited gain in aerobic capacity in response to training in the octogenarians.
近期证据表明，八旬老人对训练的适应性减弱，其峰值耗氧量（VO₂）仅有小幅增加，这是由心输出量适度改善介导的，而动静脉氧含量差并未增加。本研究旨在确定八旬老人峰值VO₂和心输出量增加减少是否与缺乏左心室和动脉对运动训练的适应性有关。我们研究了22名八旬老人（81.9±3.7岁，均值±标准差），随机将其分为一组，以峰值心率的82.5±5%的强度进行9个月的运动，另有14名（年龄83.1±4.1岁）被分配到对照组。运动组的峰值VO₂增加了12%，而对照组则略有下降（-7%）。运动组在绝对工作率的次最大运动期间，心率（6%，P = 0.002）和心率-压力乘积（9%，P = 0.004）显著但小幅下降。通过二维超声心动图评估，训练并未引起左心室大小、几何形状（壁厚与半径比）、质量和功能的显著变化，通过压平式眼压计评估，训练也未引起动脉僵硬度的显著变化。数据表明，缺乏心脏和动脉适应性可能部分解释了八旬老人在训练后有氧能力增加有限的原因。
