['During reactive hyperemia, the brachial artery in some individuals constricts prior to dilation. Our aim was to describe the frequency of high-flow-mediated constriction (H-FMC) in adults, and its relationship to body composition and biomarkers of cardiovascular and metabolic risk.', 'Two hundred forty-six adults (124 male, 122 female; 36\u2009±\u20097 years old) were assessed for H-FMC via sonographic imaging of the brachial artery. Blood pressure, glucose, insulin, lipids, and body composition assessed via dual energy X-ray absorptiometry were collected. H-FMC was characterized as a 10-second average of maximal postocclusion constriction. Independent t test was used to compare H-FMC versus non-H-FMC individuals.', 'H-FMC was observed in approximately 69% of adult participants (54 obese, 57 overweight, and 59 normal weight). Total body mass (82.3\u2009±\u200917.5 versus 76.3\u2009±\u200916.3 kg, p\u2009=\u20090.012), fat mass (27.7\u2009±\u200911.5 versus 23.8\u2009±\u200910.5 kg, p\u2009=\u20090.012), body mass index (27.7\u2009±\u20094.9 versus 26.1\u2009±\u20095.0 kg/m'] Is high-flow-mediated constriction in adults influenced by biomarkers of cardiovascular and metabolic risk?