Abstract
Regular physical activity and endurance exercise training prevent age-related vascular endothelial dysfunction in the arm in men. However, the effects of physical activity and/or endurance exercise training in the legs, which have a greater predisposition for vascular disease, have not been completely elucidated. This study sought to examine the impact of aging, physical activity, and endurance exercise training on leg vascular function in men. Flow-mediated dilation (FMD) of the superficial femoral and popliteal arteries (SFA and PA, respectively) was assessed in a total of 39 men, comprised of 10 young sedentary (Y; 23 ± 2 yr), 8 older sedentary (OS; 76 ± 8 yr), 9 older physically active (OA; 71 ± 8 yr), and 12 older endurance exercise trained (OT) subjects with exceptional aerobic exercise capacity (V̇o(2max)) for their age (70 ± 3 yr, V̇o(2max) = 53 ± 6 mL·kg(-1)·min(-1)). FMD was lower in the OS group compared with the Y in the SFA (Y: 4.3 ± 2.1%, OS: 1.7 ± 1.0%, P = 0.005) and PA (Y: 5.8 ± 2.4%, OS: 1.9 ± 1.1%, P < 0.05). SFA and PA FMD were not different from OS in the OA group (SFA: 2.8 ± 1.5%; PA: 1.6 ± 1.0%) but were higher than OS in the OT group (SFA: 3.4 ± 2.3%, P = 0.043; PA: 4.2 ± 3.0%, P = 0.025) and not different from Y. There was evidence of a moderate-strong correlation between SFA (r = 0.32, P = 0.052) and PA (0.36, P = 0.037) FMD and V̇o(2max) but not physical activity levels. These findings suggest that habitual physical activity in general, and endurance exercise training in particular, diminishes the detrimental effect of aging on lower limb vascular function in men, and this may be linked to an augmented V̇o(2max).NEW & NOTEWORTHY In the current study, we provide evidence of a relation between high levels of physical activity associated with lifelong endurance exercise training and protection from age-related declines in vascular endothelial function in the lower limb in men. Moreover, our findings suggest that aerobic fitness, in particular, may confer the benefits of endurance exercise training in maintaining lower limb endothelial function with advancing age.