Modern Cycling: part sport, part science

ABSTRACT Exaggerated systolic blood pressure (SBP) responses to graded exercise testing in normotensive adults have been associated with risk of future hypertension. Endothelial dysfunction is one of the mechanisms that lead to functional and structural changes in resistance vessels. Venous occlusion plethysmography (VOP) non-invasively characterizes endothelium-dependent vasodilatory capacity in peripheral arteries (reactive hyperemia: RH). PURPOSE: To determine if an association exists between exaggerated SBP responses to graded exercise and peripheral vascular vasodilatory capacity. METHODS: Subjects were 50 young males (Mean ± SD: age = 22.4 ± 2.6 yr; body fat = 24.3 ± 6.1 %; BMI = 27.7 ± 5.7). Post-occlusive RH was assessed after a 5-min brachial artery occlusion using VOP and standard procedures recommended by the manufacturer (Hokanson EC-6, Bellevue, WA). Each subject performed maximal cycle ergometer exercise tests with a 15 watts/min ramping protocol. Blood pressures (BP) were measured at rest, every 2 min during, and at 15 sec intervals after exercise. RESULTS: During exercise, no relationship was found between any of the exaggerated SBP indices and the measures of peripheral artery status by VOP. Furthermore, when individual SBP responses from peak exercise at the highest vs. lowest tertiles were contrasted, no differences in the VOP measures of vascular status were found. CONCLUSION: Exaggerated SBP response to graded exercise in young adult males seems to be regulated largely by factors other than peripheral vascular status, as assessed by VOP/RH.