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Postprandial hyperglycemia (PPH) impairs vascular endothelial function (VEF). A single bout of aerobic exercise (AE) attenuates PPH-induced decreases in brachial artery flow-mediated dilation (FMD), a non-invasive measure of VEF, in healthy adults for up to 17 h post-exercise. Studies examining the effects of resistance exercise (RE) on postprandial FMD responses are lacking. We hypothesized that a single bout of exercise performed the prior evening would attenuate PPH-induced decreases in FMD, independent of exercise modality. In a randomized, cross-over design, overweight/obese adults [n = 11 (8 women); 22 ± 4 years; 32.3 ± 5.8 kg m−2] completed 3 separate trials: control (seated rest), AE (30 min at ~ 60% VO2max), or whole-body RE (30 min, 6 exercises, 3 × 10-repetition maximum). Each trial occurred 14–17 h prior to an oral glucose tolerance test (OGTT). Brachial artery FMD and plasma glucose and insulin were measured prior to and at 30-min intervals for 2 h following the OGTT. Repeated-measures ANOVA and Bonferroni post hoc tests were used to evaluate differences within and between trials. Trials occurred 15.3 ± 1.0 h prior to the OGTT. Relative to baseline, FMD transiently decreased (P

Acute aerobic exercise prevents sitting-induced impairment of flow-mediated dilation (FMD). Further, evidence suggests that sitting-induced impairment of FMD occurs via an oxidative stress-dependent mechanism that disrupts endothelial function. We hypothesized that acute aerobic exercise would prevent impairment of femoral artery FMD by limiting oxidative stress responses that increase endothelin-1 (ET-1) levels and disrupt nitric oxide (NO) status. In a randomized, cross-over study, healthy men (n = 11; 21.2 ± 1.9 years) completed two 3 h sitting trials that were preceded by 45 min of either quiet rest (REST) or a single bout of continuous treadmill exercise (65% maximal oxygen consumption) (EX). Superficial femoral artery FMD, plasma glucose, malondialdehyde (MDA), ET-1, arginine (ARG) and its related metabolites [homoarginine (HA), asymmetric dimethylarginine (ADMA), symmetric dimethylarginine (SDMA)] were assessed at baseline, 1 h following EX (or REST) (0 h), and at 1 h intervals during 3 h of uninterrupted sitting. Data were analyzed using repeated measures ANOVA. During REST, femoral artery FMD declined from baseline (2.6 ± 1.8%) at 1, 2, and 3 h of sitting and resting shear rate decreased at 3 h. In contrast, when sitting was preceded by EX, femoral artery FMD (2.7 ± 2.0%) and resting shear rate responses were unaffected. No between trial differences were detected for plasma glucose, MDA, ET-1, ARG, HA, ADMA, or SDMA. Prior aerobic exercise prevented the decline in femoral artery FMD that is otherwise induced by prolonged sitting independent of changes in oxidative stress, ET-1, and NO status.

We assessed the impact of completing the Hotter’n Hell Hundred (HHH), an annual 164 km road cycling event performed in a hot environment, on hemostatic balance in men. Sixteen men who completed the ride in