Physical training improves flow-mediated dilation in patients with the polymetabolic syndrome

Endothelial dysfunction that can be detected as impaired flow-mediated dila tion by ultrasonography is an early event in atherogenesis and has been dem onstrated in healthy subjects with risk factors for atherosclerosis many ye ars before the appearance of atheromatous plaques. We examined the influenc e of physical training on flow-mediated dilation in patients with the polym etabolic syndrome. Twenty-nine asymptomatic men aged 40 to 60 years with th e polymetabolic syndrome were randomly divided between the control group an d the training group, which trained 3 times a week for 12 weeks. On high-re solution ultrasound images, the diameter of the brachial artery was measure d at rest, after reactive hyperemia (causing flow-mediated, endothelium-dep endent dilation), and after sublingual glyceryltrinitrate (causing endothel ium-independent vasodilation) in all subjects before and after the training period. The training program induced an increase of 18% in physical fitnes s. Flow-mediated dilation increased from 5.3+/-2.8% to 7.3+/-2.7% (P<0.05). There was no change in body mass index, blood pressure, insulin resistance , lipids, and big endothelin-l in either group, Flow-mediated dilation meas ured before training was negatively correlated with resting heart rate, wai st-to-hip ratio, and insulin resistance. Resting heart rate emerged as the only independent determinant, which explained 22% of the variation in flow- mediated dilation. In conclusion, our findings suggest that a 3-month physi cal training program, which improved maximal exercise capacity, enhances fl ow-mediated dilation in patients with the polymetabolic syndrome.