Yun Sung Ho, Choi Jang Kyu, Park Yang Saeng
Department of Physiology, Kosin University College of Medicine, 34 Amnam-dong, Seo-gu, 602-702 Busan, South Korea.
Eur J Appl Physiol. 2004 May;91(5-6):708-11. doi: 10.1007/s00421-003-1010-4. Epub 2004 Feb 10.
Head-out water immersion (HOI) increases cardiac output (CO) for a given oxygen consumption. To investigate whether professional breath-hold divers show a similar response, cardiovascular responses to HOI were compared between six Korean women breath-hold divers, six non-diving housewives and six non-diving young women at rest and while performing leg cycle exercise of moderate intensity (Deltametabolic rate = approximately 100 W m(-2)) in water at a thermoneutral temperature (34.5 degrees C). In all three groups, HOI increased CO markedly due to a rise in stroke volume, with no significant change in heart rate (HR) and arterial blood pressure (BP). Thus, total peripheral resistance (TPR) and arterio-venous oxygen content difference fell significantly. During dynamic exercise in water CO increased mainly due to a rise in HR. The arterial systolic BP rose slightly with no significant change in diastolic BP, and the TPR fell 20-40% with similar responses among the three groups of subjects. This study showed that both at rest and during exercise, cardiovascular responses to immersion do not vary significantly with age and water immersion experience.
头部浸入水中（HOI）在给定耗氧量的情况下会增加心输出量（CO）。为了研究职业屏气潜水员是否有类似反应，我们比较了六名韩国女性屏气潜水员、六名非潜水家庭主妇和六名非潜水年轻女性在静息状态以及在热中性温度（34.5摄氏度）的水中进行中等强度腿部循环运动（代谢率变化约为100 W m(-2)）时对HOI的心血管反应。在所有三组中，HOI均因每搏输出量增加而显著增加心输出量，心率（HR）和动脉血压（BP）无显著变化。因此，总外周阻力（TPR）和动静脉氧含量差显著下降。在水中进行动态运动时，心输出量增加主要是由于心率升高。动脉收缩压略有上升，舒张压无显著变化，三组受试者的总外周阻力下降20 - 40%，反应相似。这项研究表明，无论是在静息状态还是运动过程中，对浸入的心血管反应不会因年龄和浸水经验而有显著差异。
