Hernandez Juliane P, Franke Warren D
Dept. of Physical Education, Southern Illinois Univ., 109 Davies Hall, mail code 4310, Carbondale, IL 62901-4310, USA.
J Appl Physiol (1985). 2005 Sep;99(3):1070-7. doi: 10.1152/japplphysiol.01169.2004. Epub 2005 Apr 14.
Aging and chronic exercise training influence leg venous compliance. Venous compliance affects responses to an orthostatic stress. The extent to which exercise training in a previously sedentary older population will affect venous compliance and tolerance to the simulated orthostatic stress of maximal lower body negative pressure (LBNP) is unknown. The purpose of this investigation is to determine the influence of a 6-mo endurance-training program on calf venous compliance and responses and tolerance to maximal LBNP in older men and women. Twenty participants (exercise group: n = 10, 5 men, 5 women; control group: n = 10, 6 men, 4 women; all >60 yr) underwent graded LBNP to presyncope or 4 min at -100 mmHg before and after a 6-mo endurance-training program. Utilizing venous occlusion plethysmography, calf venous compliance was determined in both groups using the first derivative of the pressure-volume relation during cuff pressure reduction before training, at 3 mo, and at the end of the training program. The exercise group improved their fitness with the 6-mo endurance-training program, whereas the control group did not change (14 +/- 3 vs. <1 +/- 2%; P < 0.05). LBNP tolerance did not differ between groups or across trials (P = 0.47). Venous compliance was not different between groups or trials, either initially or after 3 mo of endurance training, but tended to be greater in the exercise group after 6 mo of training (P = 0.08). These data suggest that a 6-mo endurance-training program may improve venous compliance without affecting tolerance to maximal LBNP in older participants.
衰老和长期运动训练会影响腿部静脉顺应性。静脉顺应性会影响对直立位应激的反应。之前久坐不动的老年人群进行运动训练对静脉顺应性以及对最大下肢负压（LBNP）模拟直立位应激的耐受性的影响程度尚不清楚。本研究的目的是确定一项为期6个月的耐力训练计划对老年男性和女性小腿静脉顺应性以及对最大LBNP的反应和耐受性的影响。20名参与者（运动组：n = 10，5名男性，5名女性；对照组：n = 10，6名男性，4名女性；均>60岁）在进行为期6个月的耐力训练计划前后，接受分级LBNP直至出现前驱晕厥或在-100 mmHg下持续4分钟。利用静脉阻塞体积描记法，在训练前、3个月时和训练计划结束时，通过袖带压力降低期间压力-容积关系的一阶导数，测定两组的小腿静脉顺应性。运动组通过6个月的耐力训练计划提高了身体素质，而对照组没有变化（14±3 vs. <1±2%；P<0.05）。两组之间或不同试验中的LBNP耐受性没有差异（P = 0.47）。无论是初始时还是耐力训练3个月后，两组之间或不同试验中的静脉顺应性均无差异，但在训练6个月后，运动组的静脉顺应性有增加的趋势（P = 0.08）。这些数据表明，一项为期6个月的耐力训练计划可能会改善老年参与者的静脉顺应性，而不影响其对最大LBNP的耐受性。
