The Effects of Moderate‐to‐Vigorous Physical Activity on Arterial Stiffness during Pregnancy

Abstract

Moderate-to-vigorous physical activity (MVPA) is associated with lower arterial stiffness in the general population. The objective of the present study was to investigate the relationship between MVPA and arterial stiffness in pregnancy. Thirty-nine women participated in this study resulting in 68 measurements in non-pregnant (NP; n=21), first (TM1; n=8), second (TM2; n=20), and third trimesters (TM3; n=19). Carotid to femoral (central) and carotid to finger (peripheral) pulse wave velocity (PWV) were assessed using finometer (proper digital artery), tonometer (carotid artery), and ultrasound (femoral artery). Carotid artery distensibility, compliance, elasticity, and ß-stiffness were calculated from carotid artery diameters at diastole and systole from three ultrasound images of the right carotid artery assessed using manual digital calipers. MVPA was measured during the waking hours of 7-consecutive days using accelerometry (Actigraph; model wGT3X-BT). Freedson accelerometer counts for MVPA were ≥ 1,952 cmp. Comparisons between pregnant and non-pregnant participants and according to gestational age (in pregnant participants only) were performed using multilevel linear regression models adjusted for multiple tests per participant during the study period (NP, TM1, TM2, or TM3) using random effects for modelling intra-cluster correlation to generate β coefficients and 95% confidence intervals (CI). Carotid artery distensibility, elasticity, and β-stiffness were not statistically different between the NP, TM1, TM2, and TM3 phases. However, carotid compliance was higher in TM2 compared to NP. Central and peripheral PWV did not differ between pregnant and non-pregnant participants. Though, meeting the MVPA guidelines (≥150minutes per week) was associated with a decrease in both central PWV (Adj. β coef.: -0.30; 95% CI: -0.58, -0.02, p=0.04) and peripheral PWV (Adj. β coef.: -0.54; 95% CI: -0.91, -0.16, p=0.005) in pregnant and non-pregnant assessments. Central PWV (β Coef: -0.14, 95% CI: -0.27, -0.02, p=0.024; n=42), varied according to gestational age with a decrease in mid-pregnancy and subsequent increase to late pregnancy while gestational age was not significantly associated with peripheral PWV. Adjustment for meeting the MVPA guidelines (β Coef: -0.34, 95% CI: -0.62, -0.06, p=0.016) reduced the association between gestational age and central-PWV (Figure 1). These results suggest that there is a relationship between MVPA and arterial stiffness throughout pregnancy. This may explain a proportion of the correlation between increased physical activity and a reduced risk of hypertension-related disorders in pregnancy.