When and How Should Chinese Pregnant Women Exercise? A Longitudinal Study in China

Abstract

This study aimed to examine when and how physical activity (PA) influences gestational weight gain (GWG) and infant birthweight (BW) by considering the PA’s total volume, timing, intensity, and type, controlling for the influence of energy intake. A total of 1272 participants in different stages of pregnancy were recruited from hospital. The associations between PA and GWG or BW in the latter half of pregnancy were significant. Women with the highest PA volume in the third trimester had significantly lower risks of inadequate and excessive GWG by 69% (OR = 0.31, 95%CI: 0.10–0.91) and 67% (OR = 0.33, 95% CI: 0.12–0.91), respectively, compared to women in the lowest quartile. Women who achieved the recommended moderate intensity of PA during their second and third trimesters, independent of total volume of PA, had infants with significantly lower BWs compared to those who did not (β = −0.15, SE = 66.33, p = 0.04; β = −0.20, SE = 64.54, p = 0.01, respectively). Therefore, the effects of total volume and intensity of PA on GWG and BW were different. Interventions to prevent inappropriate GWG and macrosomia may need to set different priorities and timing regarding total volume or intensity of PA.

Impact of energy availability and physical activity on variation in fertility across human populations

“…These effects are consistent with the view that energy expended in physical activity trades off against energy available for reproductive function. While reproductive health and pregnancy outcomes for athletes are largely understudied, there is some evidence for reduced gestational weight gain and neonatal body size among athletes and nonathletes who exercise regularly [98][99][100].…”

“…These are important goals, but a more ecological and anthropological perspective may improve our understanding of the connections between lifestyle and reproductive outcomes. For example, while physical activity is known to improve cardiorespiratory and metabolic health, few studies have collected objective measures of physical activity alongside measures of energy expenditure during pregnancy or postpartum, and the role of physical activity in shaping energy allocation to reproduction remains understudied [98][99][100]105]. Studies of pregnancy and postpartum energetics in athletes may be particularly fruitful, as their prodigious exercise workloads could provide a test of energetic limits hypotheses for human reproduction and enable researchers to identify energy trade-offs and other impacts of physical activity [34,35].…”