Exercise training and artery function in humans: nonresponse and its relationship to cardiovascular risk factors

Abstract

The objectives of our study were to examine 1) the proportion of responders and nonresponders to exercise training in terms of vascular function; 2) a priori factors related to exercise training-induced changes in conduit artery function, and 3) the contribution of traditional cardiovascular risk factors to exercise-induced changes in artery function. We pooled data from our laboratories involving 182 subjects who underwent supervised, large-muscle group, endurance-type exercise training interventions with pre-/posttraining measures of flow-mediated dilation (FMD%) to assess artery function. All studies adopted an identical FMD protocol (5-min ischemia, distal cuff inflation), contemporary echo-Doppler methodology, and observer-independent automated analysis. Linear regression analysis was used to identify factors contributing to changes in FMD%. We found that cardiopulmonary fitness improved, and weight, body mass index (BMI), cholesterol, and mean arterial pressure (MAP) decreased after training, while FMD% increased in 76% of subjects (P < 0.001). Training-induced increase in FMD% was predicted by lower body weight (β = -0.212), lower baseline FMD% (β = -0.469), lower training frequency (β = -0.256), and longer training duration (β = 0.367) (combined: P < 0.001, r = 0.63). With the exception of a modest correlation with total cholesterol (r = -0.243, P < 0.01), changes in traditional cardiovascular risk factors were not significantly related to changes in FMD% (P > 0.05). In conclusion, we found that, while some subjects do not demonstrate increases following exercise training, improvement in FMD% is present in those with lower pretraining body weight and endothelial function. Moreover, exercise training-induced change in FMD% did not correlate with changes in traditional cardiovascular risk factors, indicating that some cardioprotective effects of exercise training are independent of improvement in risk factors.

Microvascular Endothelial Dysfunction in Sedentary, Obese Humans Is Mediated by NADPH Oxidase

“…34 In the present study, we observed significant decreases in both total and Nox-mediated H 2 O 2 in the obese skeletal muscle extracellular environment post-training. Despite no AIT-induced changes in the traditional cardiovascular risk factors, we observed augmented microvascular endothelial function in the obese group, while apocynin no longer affected endothelial function post-training.…”

Exercise and Vascular Function in Child Obesity: A Meta-Analysis

“…19,43 Improvements in endothelium-dependent function can occur independently of improvements in risk factors such as blood lipids, blood pressure, obesity, and glycemic control. 44,45 Although exercise training has been shown to improve vascular function in both animals and humans, these changes are rapidly lost after the cessation of training. 46 In patients with a recent myocardial infarction, 4 weeks of exercise training resulted in significant improvements in endothelium-dependent dilation.…”

Cardiovascular Adaptations to Exercise Training

“…Nevertheless, other vascular function tests, such as reactive hyperemia, flow-mediated dilatation (FMD) and infusion of vasodilators are useful in that they test mainly one vasodilating mechanism and the effect or role of only one or a few vasodilator compounds. Such tests therefore allow for more specific insight into vasoregulatory mechanisms than exercise and particularly FMD has been proven useful as predictor of cardiovascular disease (142). FMD is commonly measured in the brachial artery and assessed as the change in vessel diameter that occurs after a period of forearm occlusion induced by use of a cuff (57).…”

“…FMD is commonly measured in the brachial artery and assessed as the change in vessel diameter that occurs after a period of forearm occlusion induced by use of a cuff (57). A large number of studies have been conducted in which the effect of training on FMD has been evaluated in different populations with an emphasis not only on individuals at risk for cardiovascular disease (142), but also in healthy young individuals (309,409). Cardiovascular risk groups generally experience marked improvements in FMD with exercise training (426) whereas the effects are less clear in young healthy controls (146).…”