Influence of Aerobic Fitness on Vasoreactivity in Young Men
Previous work has demonstrated a direct relationship between aerobic fitness and vasodilatory function (i.e., flow-mediated dilation; FMD); however, the relation between aerobic fitness and vasoconstrictor responsiveness (i.e., low flow-mediated constriction; L-FMC), and the overall vasoactive range (FMD + L-FMC) is unclear. Purpose To test the hypothesis that L-FMC and the overall vasoactive range (FMD + L-FMC) will be related to aerobic fitness in young, healthy men. Methods Twenty men (age: 23 +/- 5 years) were recruited, and divided evenly into a higher (HF) vs. lower (LF) aerobic fitness group, quantified via YMCA cycle ergometry (VO2 peak extrapolation), and a 3-min step test (1-min heart rate recovery). Duplex Doppler-ultrasound was used to assess brachial artery FMD and L-FMC. Results Estimated VO2 peak (HF = 55 +/- 10 vs. LF = 38 +/- 5 mL/kg/min) and heart rate recovery (HF = 36 +/- 10 vs. LF = 25 +/- 8 beats) were greater in the HF group (P < 0.05). FMD and the vasoactive range were similar between groups; however, L-FMC was significantly greater in HF (HF = -2.5 +/- 1.6 vs. LF = -0.7 +/- 1.8%, P < 0.05; d = 1.18). A correlational analysis revealed an inverse relationship between L-FMC and both HR recovery (r = -0.665, P < 0.01) and estimated VO2 peak (r = -0.5, P < 0.05). Conclusions This work supports an association between L-FMC and aerobic fitness in young, healthy men. Longitudinal or interventional studies are warranted to support causality, and to distinguish whether L-FMC is more sensitive to changes in aerobic fitness than FMD.
European Journal of Applied Physiology
Bell, P. L.,
Kelley, E. T.,
McCoy, S. M.,
Credeur, D. P.
(2017). Influence of Aerobic Fitness on Vasoreactivity in Young Men. European Journal of Applied Physiology, 117(10), 2075-2083.
Available at: https://aquila.usm.edu/fac_pubs/17633