Sympathoadrenal-circulatory regulation during sustained isometric exercise in young and older men.
Sympathoadrenal-circulatory regulation during sustained isometric exercise in young and older men.
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年轻和老年男性持续等长运动期间的交感肾上腺循环调节。
DOI：
10.1152/ajpregu.1991.261.5.r1061
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Seals,DR
中科院分区：
文献类型：
--
作者：
Taylor,JA;Hand,GA;Johnson,DG;Seals,DR
本研究的目的是检验这一假设，即动脉血压，血管收缩剂，和交感肾上腺调节持续次最大等长运动成为增强与人类年龄的增长。14名年轻（26 +/- 1岁）和14名老年（66 +/- 1岁）健康男性进行等长握力锻炼，最大随意力量的30%，直到筋疲力尽（无法维持目标力）。年轻受试者和老年受试者的最大握力非常相似（分别为402 +/- 20和392 +/- 20 N）。两组在休息时的任何变量上均无显著差异。在持续的握到筋疲力尽的过程中，年轻人和老年人的感知用力和收缩前臂肌电活动的峰值水平相似，这表明他们的自愿努力是相等的。两组的运动时间没有差异（年轻男性为315 +/- 27秒，老年男性为339 +/- 17秒）。在整个运动过程中，年轻人和老年人的动脉血压升高非常相似。老年男性心率增加较少（P <0.05），但每搏输出量（阻抗心动图）减少较少（不显著）;因此，两组心输出量增加无差异。在运动的后半部分，年轻和老年男性的全身血管阻力都有增加的趋势，没有显著的组间差异。在整个小腿（静脉闭塞体积描记法）和小腿皮肤（激光多普勒测速仪）的血流反应是相似的，在年轻和老年受试者，血管阻力的相应增加。（250字处删节）
The aim of this study was to test the hypothesis that the arterial blood pressure, vasoconstrictor, and sympathoadrenal adjustments to sustained submaximal isometric exercise become augmented with advancing age in humans. Fourteen young (26 +/- 1 yr) and 14 older (66 +/- 1 yr) healthy males performed isometric handgrip exercise at 30% of maximal voluntary force until exhaustion (inability to maintain target force). Maximal handgrip force was quite similar in the young and older subjects (402 +/- 20 vs. 392 +/- 20 N, respectively). The two groups did not differ significantly on any variable at rest. During sustained handgrip to exhaustion, peak levels of both perceived exertion and contracting forearm electromyographic activity were similar in the young and older men, suggesting equivalent voluntary efforts. Exercise time was not different in the two groups (315 +/- 27 s in young vs. 339 +/- 17 s in older men). Throughout exercise the increases in arterial blood pressure were very similar in the young and older subjects. Heart rate increased less (P less than 0.05), but stroke volume (impedance cardiography) tended to decrease less (not significant) in the older men; thus the increases in cardiac output were not different in the two groups. During the latter portion of exercise, systemic vascular resistance tended to increase in both the young and older men, with no significant group differences. The blood flow responses in the whole calf (venous occlusion plethysmography) and the calf skin (laser-Doppler velocimetry) were similar in the young and older subjects, as were the corresponding increases in vascular resistance.(ABSTRACT TRUNCATED AT 250 WORDS)