Acute exercise effects on vascular and autonomic function in overweight men

The acute effect of a single bout of aerobic exercise on vascular and cardiac autonomic function of overweight males was investigated. Fifteen normal weight (NW) and 15 overweight (OW) males had their vascular and cardiac function assessed before and after a 30-min bout of cycling exercise performed at 65% of maximal oxygen uptake. Forearm blood flow (FBF) was assessed using Hokanson Plethysmography with occlusion technique. Forearm vascular resistance (FVR) was determined by dividing mean arterial pressure by FBF. Arterial stiffness was assessed using applanation tonometry through pulse wave velocity (PWV) and augmentation index (AIx), a measure of wave reflection, which was calculated as the ratio of augmented pressure and pulse pressure. Autonomic function was assessed through baroreceptor sensitivity (BRS) and heart rate variability (HRV). FBF was increased in both groups, NW: from 2.57 ± 0.18 to 4.98 ± 0.49 and OW: from 3.16 ± 0.29 to 4.11 ± 0.27. The increase in FBF was also accompanied by a decrease in FVR by 46 % in NW (from 34.5 ± 2.76 to 18.5 ± 2.79) and by 29 % in OW (from 28.2 ± 2.32 to 19.9 ± 1.53) P < 0.05. There were no changes in PWV, BRS, and HRV at post exercise. AIx, however, was increased in both groups, NW: from -4.53 ± 2.72 to 2.60 ± 1.46 and OW: from 4.46 ± 2.43 to 10.5 ± 1.90. Overweight compared to normal weight males failed to increase FBF after exercise which indicated inhibited vasodilation.