Exercise-Induced Heat Stress Disrupts the Shear-Dilatory Relationship
endothelial, flow mediated dilation, heat, hemodynamics, reactive hyperemia, vascular
What is the central question of this study?
Although heat stress is known to increase cardiovascular strain, no study, to date, had explored the potential impact of exercise-induced heat stress on vascular function.
What is the main finding and its importance?
We found that acute exercise tended to reduce flow-mediated dilatation (FMD), owing in part to reduced reactive hyperaemia/shear stimulus; thus, when FMD is normalized to shear no postexercise deficit exists. Exercise-induced heat stress increased reactive hyperaemia, shear rate, coupled with a sustained FMD postexercise, suggests that exercise-induced heat stress increases the amount of shear stimulus to elicit a similar response, indicating reduced vascular responsiveness, or reserve, which might increase cardiovascular susceptibility.
Ives SJ, Lefferts WK, Wharton M, Fehling PC, Smith DL. Exercise-induced heat stress disrupts the shear-dilatory relationship. Exp Physiol. 2016 Dec 1;101(12):1541-1551. doi: 10.1113/EP085828. [Epub ahead of print Sep 20] PubMed PMID: 27647442.