Effects of aerobic interval training on arterial stiffness and microvascular function in patients with metabolic syndrome.

The authors determined the effect of high-intensity aerobic interval training on arterial stiffness and microvascular dysfunction in patients with metabolic syndrome with hypertension. Applanation tonometry was used to measure arterial stiffness and laser Doppler flowmetry to assess microvascular dysfunction before and after 6 months of stationary cycling (training group; n = 23) in comparison to a group that remained sedentary (control group; n = 23). While no variable improved in controls, hypertension fell from 79% (59%-91%) to 41% (24%-61%) in the training group, resulting in lower systolic and diastolic pressures than controls (-12 ± 3 and -6 ± 2 mm Hg, P < .008). Arterial stiffness declined (-17% augmentation index, P = .048) and reactive hyperemia increased (20%, P = .028) posttreatment in the training group vs controls. Blood constituents associated with arterial stiffness and a prothrombotic state (high-sensitivity C-reactive protein, fibrinogen, platelets, and erythrocytes) remained unchanged in the training and control groups. In summary, 6 months of an intense aerobic exercise program reduced both arterial stiffness and microvascular dysfunction in patients with metabolic syndrome despite unchanged blood-borne cardiovascular risk factors. Training lowers blood flow resistance in central and peripheral vascular beds in a coordinated fashion, resulting in clinically relevant reductions in hypertension.