Blood pressure reactivity to mental stress and aerobic fitness in normotensive young adult African–American males with parental history of hypertension

Hypertension (HT) is the leading health problem in the adult African–American (AA) community and is associated with risk factors of stress, physical inactivity, and family history. We examined the influences of aerobic fitness and parental history of HT on blood pressure (BP) reactivity to mental stress in 60 normotensive young adult AA males. A 5‐min mental arithmetic test was used as a provocative stress. Measurements of peak oxygen uptake (V̇O_2peak) were used to classify physically active and inactive subjects into groups of high and low aerobic fitness. A questionnaire was used to evaluate parental BP histories. Reactivity of BP was indexed by differences in values (delta) measured during baseline and stress testing periods. Subjects with a parental history of HT (PH⁺) had significantly higher baseline systolic BP and mean arterial BP (SBP, MABP) values than subjects with no parental history of HT (PH⁻). Among the group of PH⁺ subjects, BP reactivity to mental stress was as follows: the high aerobic fitness subgroup (V̇O_2peak=54.6±1.2 ml/kg/min) (n=15) exhibited a 7.3±2.0 mmHg rise in SBP and a 3.2±2.0 mmHg rise in MABP, and the low aerobic fitness subgroup (V̇O_2peak=37.1±0.7 ml/kg/min) (n=15) had a 15.8±2.0 mmHg rise in SBP and an 11.8±2.0 mmHg rise in MABP (p<0.05). Among the group of PH⁻ subjects with high and low aerobic fitness (n=30, 15/group), no differences in BP reactivity to mental stress were found. These results suggest that a lifestyle of physical activity associated with a high level of aerobic fitness may attenuate BP reactivity to mental stress and reduce the risk of HT in AA men. Copyright © 2000 John Wiley & Sons, Ltd.