In a randomized controlled trial researchers also looked at pregnancy and the risk for GDM-related adverse effects….
Five hundred ten healthy first-time pregnant mothers were randomly assigned to either an exercise intervention group or a usual care control group (255 mothers in each). The goal was to examine the effects of regular moderate-intensity exercise on the incidence of gestational diabetes mellitus (GDM) (primary outcome).
The investigators also examined whether or not the exercise intervention had an effect on the association between GDM and birth weight and risk of macrosomia, gestational age, risk of caesarean delivery and maternal weight gain (secondary outcomes).
The intervention group was placed on a 50-55 minute exercise program that focused on moderate-intensity resistance and aerobic exercises for 3 times a week. GDM was diagnosed according to the World Health Organization (WHO) criteria and the International Association for Diabetes in Pregnancy Study Group (IADPSG) criteria.
The results of the study showed that the intervention did not reduce the risk of developing GDM. However, compared to the control group, the exercise program did reduce GDM-related risk of having a newborn with macrosomia by 58%, GDM-related risk of having acute and elective caesarean delivery by 34% and maternal weight gain (independent of GDM diagnosis) by ~12%.
Gestational age was also similar across both groups. Results were similar when using the IADPSG criteria.
The study concluded that regular moderate-intensity exercise performed over the second-third trimesters of pregnancy can be used to attenuate GDM-related adverse outcomes.
Br J Sports Med. 2013 Jul;47(10):630-6. doi: 10.1136/bjsports-2012-091788. Epub 2013 Jan 30.