Effect of increased central blood volume with water immersion on plasma catecholamines during exercise
- 1 August 1990
- journal article
- research article
- Published by American Physiological Society in Journal of Applied Physiology
- Vol. 69 (2) , 651-656
- https://doi.org/10.1152/jappl.1990.69.2.651
Abstract
To examine the influence of an increase in central blood volume with head-out water immersion (WI) on the sympathoadrenal response to graded dynamic exercise, nine healthy men underwent upright leg cycle exercise on land and with WI. Plasma norepinephrine and epinephrine concentrations were used as indexes of overall sympathoadrenal activity. Oxygen consumption (VO2), heart rate, systolic blood pressure, and plasma concentrations of norepinephrine, epinephrine, and lactate were determined at work loads corresponding to approximately 40, 60, 80, and 100% peak VO2. Peak VO2 did not differ on land and with WI. Plasma norepinephrine concentration was reduced (P less than 0.05) at 80 and 100% peak VO2 with WI and on land, respectively. Plasma epinephrine and lactate concentrations were similar on land and with WI at the three submaximal work stages, but both were reduced (P less than 0.05) at peak exertion with WI. Heart rate was lower (P less than 0.05) at the three highest work intensities with WI. These results suggest that the central shift in blood volume with WI reduces the sympathoadrenal response to high-intensity dynamic exercise.This publication has 1 reference indexed in Scilit:
- Effect of central hypervolemia on cardiac performance during exerciseJournal of Applied Physiology, 1984