The effects of exercise training on markers of endothelial function in young healthy men.

This study investigated the effects of fitness and of acute exercise on a range of markers of endothelial function in young, healthy adult male subjects who were classified on the basis of maximum oxygen consumptions as being fit VO(2 peak) 71 +/- 2 [ml x min (-1)] x kg (-1) or sedentary VO(2 peak) 53 +/- 2 [ml x min (-1)] x kg (-1). Fit and sedentary subjects had similar resting plasma levels of von Willebrand factor (vWF) and thrombomodulin (TM). Acute maximal aerobic exercise doubled plasma vWF in fit subjects but had no effect in the sedentary population; plasma TM rose with acute exercise in each group but to a greater extent in the fit population. Fit subjects also had higher numbers of circulating endothelial cells (CECs) at rest and exhibited substantially greater forearm reactive hyperaemia responses following a standardized period of arterial occlusion. A cohort of sedentary subjects was given a 5-week training programme of moderate aerobic exercise on a cycle ergometer. Following this, absolute fitness was increased by only 8 % but reactive hyperaemia responses rose to values similar to those in the chronically fit group. The results suggest that both acute and chronic exercise increase endothelial turnover. Chronic exercise is also associated with enhanced endothelium-dependent dilator function and this effect becomes maximal after only a short period of moderate training.