Abstract:
Black populations account for the highest rates of cardiovascular disease (CVD)
mortality, morbidity, and subclinical indices of CVD. Studies support that there are
ethnic disparities in arterial stiffness, particularly manifested as early vascular aging.
While ethnic disparities cannot be solely explained by traditional CVD risk factors,
psychosocial factors, such as mental stress, have correlated to increased arterial
stiffness. Exercise has been mentioned as a notable therapeutic mechanism for stressrelated
stiffness. Thus, the purpose of this study was to determine the effects of an
acute bout of moderate-intensity aerobic exercise on mental stress-induced arterial
stiffness in Black young adults. METHODS: 10 apparently healthy individuals (4 male,
6 female, 22.0 ± 1.8 years and BMI 25.3 ± 3.6 kg/m2) performed 30 minutes of treadmill
exercise at 64-76% of heart rate maximum before a 5-minute mental stress task. Arterial
stiffness (measured as carotid femoral pulse wave velocity [cfPWV]) and brachial and
central hemodynamic measures (bSBP, bDBP, bPP, cSBP, cDBP, cPP, MAP, HR, AP, AIx,
AIx@75) were recorded before and after the task and compared to results gathered on
the control day (consisting of the same mental stress task without prior exercise).
Participants were randomly assigned to either the control or exercise trial first.
RESULTS: The mental stress task increased PWV, independent of exercise (main effect
for time, p < 0.001). The absolute change in PWV from pre to post 0 minutes was similar
(p > 0.05) for control (+0.43±0.39) and exercise (+0.33±0.70) trials. Mental stress had
a main effect for time (p < 0.05) in emotional responses from before and after mental
stress task in both the control and exercise trials for anger, anxiety, and overall
perceived negative emotional responses. DISCUSSION: Exercise had no effect on
preventing or reducing the mental stress-induced increases in arterial stiffness and
negative emotional responses. Data reflect blunted vasodilatory response previously
observed in the Black population. Therefore, this study echoes the CV reactivity
differences demonstrated in prior literature, emphasizing concern for CV outcomes in
this specific population.
