Prenatal exercise and cardiovascular health (PEACH) study: impact of acute and chronic exercise on cerebrovascular hemodynamics and dynamic cerebral autoregulation

We performed a randomized controlled trial measuring dynamic cerebral autoregulation (dCA) using a sit-to-stand maneuver before (SS1) and following (SS2) an acute exercise test at 16-20 wk gestation (trimester 2, TM2) and then again at 34-37 wk gestation (third trimester, TM3). Following the first assessment, women were randomized into exercise training or control (standard care) groups; women in the exercise training group were prescribed moderate intensity aerobic exercise for 25-40 min on 3-4 days per week for 14 +/- 1 wk. Resting seated mean blood velocity in the middle cerebral artery (MCAv(mean)) was lower in TM3 than in TM2 but not impacted by exercise training intervention. No metric of dCA was impacted by gestational age or exercise training during SS1. During SS2, there were greater absolute and relative decreases in mean arterial blood pressure (MAP) and MCAv(mean), but this was not impacted by the intervention. There was also no difference in the relationship between the decrease in MCAv(mean) compared with the decrease in MAP (%/%) or the onset of the regulatory response with respect to acute exercise, gestational age, or intervention; however, rate of regulation was faster in women in the exercise group following acute exercise (interaction effect, P = 0.048). These data highlight the resilience of the cerebral circulation in that dCA was well maintained or improved in healthy pregnant women between TM2 and TM3. However, future work addressing the impact of acute and chronic exercise on dCA in women who are at risk for cardiovascular complications during pregnancy is needed. NEW & NOTEWORTHY These data represent the first assessments of dynamic cerebral autoregulation in pregnancy using a sitto-stand. We used a randomized controlled trial to show dynamic cerebral autoregulation is not impacted by gestational age or by chronic exercise. However, there are larger decreases in blood pressure and cerebral blood velocity following sit-to-stand after acute exercise without adverse events. These data highlight the adaptability of the cerebral circulation during pregnancy to accommodate large changes in the cardiovascular system.