Abstract
BACKGROUND: Markers of arterial stiffness including high Augmentation Index (AIx) are associated with cardiovascular events and all-cause mortality and are reduced with exercise training. In trained individuals, the AIx response to peak exercise (exercise delta AIx75 [Ex-AIx75]) may better help identify the effect of age and sex on arterial stiffening compared with conventional resting measures. This study aimed to determine the effect, and contribution of age, sex, peak oxygen (O2) uptake (V̇O2peak), mean weekly training load and lifetime training on resting AIx75, and Ex-AIx75 of healthy aerobic trained adults.
METHODS: One hundred healthy aerobic trained adults (49 women, 51 men, being 48 younger [18-30 years], 52 older [40-60 years]) underwent non-invasive measurements of AIx75 at rest and post peak cycling exercise.
RESULTS: Resting AIx75, and Ex-AIx75 were significantly higher (P<0.001) in the older group compared to the younger group. Peak O2 uptake made the largest unique contribution to resting AIx75 (P<0.001), followed by age, height, and sex. None of the variables made a significant unique contribution to Ex-AIx75.
CONCLUSIONS: In healthy aerobic trained adults, while age and sex are unique contributors of resting AIx75, V̇O2peak makes the largest unique contribution. Therefore, increasing V̇O2peak should be a primary component to consider for individuals who want to reduce their risk of CV events.