Int J Sports Med 2013; 34(05): 409-414
DOI: 10.1055/s-0032-1323829
Physiology & Biochemistry
© Georg Thieme Verlag KG Stuttgart · New York

Effects of Exercise Intensity on Flow Mediated Dilation in Healthy Humans

G. K. Birk
1   School of Sport and Exercise Science, Exercise and Health, Liverpool John Moores University, Liverpool, United Kingdom
,
E. A. Dawson
1   School of Sport and Exercise Science, Exercise and Health, Liverpool John Moores University, Liverpool, United Kingdom
,
A. M. Batterham
2   Health and Social Care Institute, Teesside University, Middlesbrough, United Kingdom
,
G. Atkinson
2   Health and Social Care Institute, Teesside University, Middlesbrough, United Kingdom
,
T. Cable
1   School of Sport and Exercise Science, Exercise and Health, Liverpool John Moores University, Liverpool, United Kingdom
,
D.H. J. Thijssen
1   School of Sport and Exercise Science, Exercise and Health, Liverpool John Moores University, Liverpool, United Kingdom
3   Department of Physiology, Radboud University Nijmegen Medical Center, the Netherlands
,
D. J. Green
1   School of Sport and Exercise Science, Exercise and Health, Liverpool John Moores University, Liverpool, United Kingdom
4   School of Sport Science, Exercise and Health, The University of Western Australia, Crawley, Western Australia
› Author Affiliations
Further Information

Publication History



accepted after revision 15 August 2012

Publication Date:
05 October 2012 (online)

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Abstract

Previous studies have demonstrated conflicting results on the effects of acute exercise on FMD. The aim of the study was to examine brachial artery FMD before and after 3 bouts of acute exercise performed at different intensities. 10 healthy males (mean±SD age: 22±1 years) completed 30 min of cycling at 50, 70 and 85% maximal heart rate (HRmax). Brachial artery FMD and the shear rate area-under-the-curve (cuff deflation to peak dilation; SRAUC) were assessed pre- and immediately post-exercise using high-resolution echo-Doppler. A generalized estimating equation (GEE) analysis was used to estimate the effect magnitudes of exercise intensity and time (pre/post) on FMD, whilst controlling for the influence of baseline diameter and SRAUC. Both baseline diameter and SRAUC were elevated by exercise. With covariate-control of these variables, the decrease in brachial artery FMD was negligible after exercise at 50% HRmax (6.3±2.6 vs. 5.9±2.5%; 95%CI for difference:  − 0.59–1.34%) with larger decreases in FMD after exercise at 70% (6.1±1.8 vs. 4.7±1.9%; 95%CI for difference: 0.08–2.58%) and at 85% HRmax (6.6±1.6 vs. 3.6±2.2%; 95%CI: 0.41–5.42%). In conclusion, even after accounting for exercise-mediated changes in shear and baseline diameter, our data indicate that a negative relationship exists between exercise intensity and FMD.