Cardiovagal autonomic function in sedentary and trained offspring of hypertensive parents.

In young normotensive subjects, parental hypertension is associated with stiffening of the carotid artery and reduction in cardiovagal outflow and baroreflex gain. In subjects without parental hypertension regular exercise training was found to attenuate age-related reduction in carotid compliance and baroreflex gain. The aim of the present study was to test the hypothesis that regular physical activity is associated with better parameters of carotid artery elasticity, increased cardiovagal outflow and higher baroreflex gain in normotensive offspring of hypertensive parents. We studied 98 healthy, sedentary or endurance exercise trained subjects (49 men, 18-27 years of age) with or without family history of hypertension (FH(+) and FH(-), respectively) in a cross-sectional design. In the sedentary group spontaneous baroreflex indices (sequence method and spectral techniques) were lower in FH(+) subjects than in their FH(-) peers, while in trained subjects these indices were not different between FH(+) and FH(-). Furthermore, in the FH(+) group trained subjects had higher baroreflex indices than their sedentary peers, while in the FH(-) group no significant differences were found. Carotid compliance and distensibility coefficient (echo-tracking ultrasound and applanation tonometry) were not different in FH(-) sedentary and trained subjects, but were higher in FH(+) trained subjects as compared to their sedentary peers. Significant but modest relationships were found between spontaneous baroreflex indices and carotid artery elastic parameters across all subjects. Our present data indicate that in subjects with parental hypertension aerobic exercise training is associated with higher levels of cardiovagal outflow and baroreflex gain, which finding, however, is not explained by greater elasticity of the carotid artery.