Endo Masako Yamaoka, Fujihara Chizuko, Miura Akira, Kashima Hideaki, Fukuba Yoshiyuki
Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan
Department of Health Sciences, Prefectural University of Hiroshima, Hiroshima, Japan.
J Appl Physiol (1985). 2016 Jun 1;120(11):1343-8. doi: 10.1152/japplphysiol.00842.2015. Epub 2016 Feb 25.
This study investigated the combined effects of consuming a meal during postexercise hypotension (PEH) on hemodynamics. Nine healthy young male subjects performed each of three trials in random order: 1) cycling at 50% of heart rate reserve for 60 min, 2) oral ingestion of a carbohydrate liquid meal (75 g glucose), or 3) carbohydrate ingestion at 40 min after cycling exercise. Blood pressure, heart rate, cardiac output, and blood flow in the superior mesenteric (SMA), brachial, and popliteal arteries were measured continuously before and after each trial. Regional vascular conductance (VC) was calculated as blood flow/mean arterial pressure. Blood pressure decreased relative to baseline values (P < 0.05) after exercise cessation. Blood flow and VC in the calf and arm increased after exercise, whereas blood flow and VC in the SMA did not. Blood pressure did not change after meal ingestion; however, blood flow and VC significantly decreased in the brachial and popliteal arteries and increased in the SMA for 120 min after the meal (P < 0.05). When the meal was ingested during PEH, blood pressure decreased below PEH levels and remained decreased for 40 min before returning to postexercise levels. The sustained increase in blood flow and VC in the limbs after exercise was reduced to baseline resting levels immediately after the meal, postprandial cardiac output was unchanged by the increased blood flow in the SMA, and total VC and SMA VC increased. Healthy young subjects can suppress severe hypotension by vasoconstriction of the limbs even when carbohydrate is ingested during PEH.
本研究调查了在运动后低血压（PEH）期间进餐对血流动力学的综合影响。九名健康年轻男性受试者按随机顺序进行了三项试验：1）以心率储备的50%进行60分钟的骑行；2）口服碳水化合物流食（75克葡萄糖）；3）在骑行运动后40分钟摄入碳水化合物。在每项试验前后连续测量血压、心率、心输出量以及肠系膜上动脉（SMA）、肱动脉和腘动脉的血流。区域血管传导率（VC）计算为血流/平均动脉压。运动停止后血压相对于基线值下降（P<0.05）。运动后小腿和手臂的血流和VC增加，而SMA的血流和VC未增加。进餐摄入后血压未改变；然而，进餐后120分钟内肱动脉和腘动脉的血流和VC显著下降，SMA的血流和VC增加（P<0.05）。当在PEH期间进餐时，血压降至PEH水平以下，并在恢复到运动后水平之前持续下降40分钟。运动后四肢血流和VC的持续增加在进餐后立即降至基线静息水平，餐后心输出量未因SMA血流增加而改变，总VC和SMA VC增加。即使在PEH期间摄入碳水化合物，健康年轻受试者也可以通过四肢血管收缩来抑制严重低血压。
