This Article Full Text Full Text (PDF) Data Supplement Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rhéaume, C. Articles by Cléroux, J. Search for Related Content PubMed PubMed Citation Articles by Rhéaume, C. Articles by Cléroux, J. Related Collections Peripheral vascular disease Type 2 diabetes Glucose intolerance Clinical Studies Exercise/exercise testing/rehabilitation Autonomic, reflex, and neurohumoral control of circulation Endothelium/vascular type/nitric oxide

(Hypertension. 2002;39:989.)
© 2002 American Heart Association, Inc.

Scientific Contributions

Effects of Mild Exercise on Insulin Sensitivity in Hypertensive Subjects

Caroline Rhéaume; Paulo H. Waib; Yves Lacourcière; André Nadeau; Jean Cléroux

From the Hypertension (C.R., P.H.W., Y.L., J.C.) and Diabetes (A.N.) Research Units, Laval University Hospital Research Center, Québec, Canada.

Correspondence to Jean Cléroux, PhD, HDQ Research Center, 9, rue McMahon, Québec (Québec) Canada G1R 2J6. E-mail Jean.Cleroux{at}crhdq.ulaval.ca

Physical exercise increases insulin sensitivity in conditions associated with insulin resistance, such as obesity and diabetes, but little is known in this regard in hypertension. Whether postexercise changes in hemodynamics and/or changes in insulin-induced vasodilatation could contribute to a postexercise increase in insulin sensitivity in hypertensive subjects is unknown. We investigated the effects of acute physical exercise on insulin sensitivity in 10 hypertensive and 10 normotensive subjects during a control evaluation (CTRL), during lower body negative pressure (LBNP), after 30 minutes of mild bicycle exercise (POSTEX), and during LBNP after exercise (POSTEX+LBNP). Insulin-induced vasodilatation was assessed from peak forearm blood flow during the intravenous glucose tolerance test. Cardiac output (4.9±0.3 versus 5.3±0.4 L/min, mean±SEM) and insulin sensitivity (the glucose disappearance rate over insulin area under the curve: 0.91±0.07 versus 1.38±0.25 min^-1/[pmol · L^-1] · minute) were lower (both P<0.05) in hypertensive than in normotensive subjects, respectively. Cardiac output decreased during LBNP, increased during POSTEX, and was similar to control during POSTEX+LBNP in both groups. Insulin sensitivity was unchanged during LBNP, increased during POSTEX, and remained elevated during POSTEX+LBNP in hypertensive subjects, whereas it remained unchanged in normotensives. Peak forearm blood flow was significantly lower in hypertensive than in normotensive subjects, despite higher insulin levels in hypertensives, and was not modified by LBNP or exercise. In conclusion, insulin sensitivity increases after exercise in hypertensive subjects, and the increase in cardiac output does not contribute to this effect. Endogenous insulin-induced vasodilatation is reduced in hypertensive subjects, and this insulin action is not affected by physical exercise.

Key Words: exercise • hypertension, essential • insulin • vasodilatation • blood flow • cardiac output

This article has been cited by other articles:

				V. A. F. Bisquolo, C. G. Cardoso Jr., K. C. Ortega, J. L. Gusmao, T. Tinucci, C. E. Negrao, B. L. Wajchenberg, D. Mion Jr, and C. L. M. Forjaz Previous exercise attenuates muscle sympathetic activity and increases blood flow during acute euglycemic hyperinsulinemia J Appl Physiol, March 1, 2005; 98(3): 866 - 871. [Abstract] [Full Text] [PDF]

				C. Rheaume, P.-H. Waib, N'G. Kouame, A. Nadeau, Y. Lacourciere, D. R. Joanisse, J.-A. Simoneau, and J. Cleroux Effects of Intense and Prolonged Exercise on Insulin Sensitivity and Glycogen Metabolism in Hypertensive Subjects Circulation, November 25, 2003; 108(21): 2653 - 2659. [Abstract] [Full Text] [PDF]