Rivera A M, Pels A E, Sady S P, Sady M A, Cullinane E M, Thompson P D
Exercise Science Laboratories, University of Rhode Island, Kingston 02881-0810.
J Appl Physiol (1985). 1989 Feb;66(2):949-54. doi: 10.1152/jappl.1989.66.2.949.
We examined the hemodynamic factors associated with the lower maximal O2 consumption (VO2max) in older formerly elite distance runners. Heart rate and VO2 were measured during submaximal and maximal treadmill exercise in 11 master [66 +/- 8 (SD) yr] and 11 young (32 +/- 5 yr) male runners. Cardiac output was determined using acetylene rebreathing at 30, 50, 70, and 85% VO2max. Maximal cardiac output was estimated using submaximal stroke volume and maximal heart rate. VO2max was 36% lower in master runners (45.0 +/- 6.9 vs. 70.4 +/- 8.0 ml.kg-1.min-1, P less than or equal to 0.05), because of both a lower maximal cardiac output (18.2 +/- 3.5 vs. 25.4 +/- 1.7 l.min-1) and arteriovenous O2 difference (16.6 +/- 1.6 vs. 18.7 +/- 1.4 ml O2.100 ml blood-1, P less than or equal to 0.05). Reduced maximal heart rate (154.4 +/- 17.4 vs. 185 +/- 5.8 beats.min-1) and stroke volume (117.1 +/- 16.1 vs. 137.2 +/- 8.7 ml.beat-1) contributed to the lower cardiac output in the older athletes (P less than or equal 0.05). These data indicate that VO2max is lower in master runners because of a diminished capacity to deliver and extract O2 during exercise.
我们研究了与老年前精英长跑运动员较低的最大摄氧量（VO2max）相关的血流动力学因素。在11名老年男性（66±8[标准差]岁）和11名年轻男性（32±5岁）跑步者进行次最大强度和最大强度跑步机运动期间，测量了心率和VO2。使用乙炔重呼吸法在VO2max的30%、50%、70%和85%时测定心输出量。使用次最大搏出量和最大心率估算最大心输出量。老年跑步者的VO2max降低了36%（45.0±6.9 vs. 70.4±8.0 ml·kg-1·min-1，P≤0.05），这是由于最大心输出量较低（18.2±3.5 vs. 25.4±1.7 l·min-1）和动静脉氧差较低（16.6±1.6 vs. 18.7±1.4 ml O2·100 ml血液-1，P≤0.05）。最大心率降低（154.4±17.4 vs. 185±5.8次·分钟-1）和搏出量降低（117.1±16.1 vs. 137.2±8.7 ml·次-1）导致老年运动员的心输出量较低（P≤0.05）。这些数据表明，老年跑步者的VO2max较低是因为运动期间输送和摄取氧气能力下降。
