Exercise During Pregnancy for Smaller Baby
Moderate Exercise During Pregnancy Lowers Baby's Birth Weight, May Reduce Baby's Risk of Obesity
WebMD News Archive
Exercise During Pregnancy: Results continued...
Researchers initially believed the exercising mothers would become less
insulin-resistant. Typically, Baldi says, a woman becomes more
insulin-resistant during pregnancy, a normal occurrence within certain
boundaries. "It has a lot to do with hormonal changes," he says. If a woman
becomes too insulin-resistant, gestational diabetes can occur.
"It did not come out as we suspected," Baldi tells WebMD, with no
substantial differences found in insulin resistance between the two groups.
The difference, says Baldi and Hofman, may be because of other factors, such
as differences found in certain growth factors. Another possible explanation,
Hofman says, is slightly reduced blood flow that occurs to the placenta during
exercise and for several hours afterward.
Exercise During Pregnancy: Other Input
The finding of lower birth weights of infants of exercising mothers is not
surprising to Linda May, PhD, an associate professor of anatomy at the Kansas
City University of Medicine and Biosciences in Kansas City, Mo., who has also
researched the topic.
The finding that there was no change in insulin sensitivity between groups
was surprising, she tells WebMD.
Her research has found that during pregnancy, more exercise [within
recommended amounts for an individual] yields more benefits.
More study is needed on high-risk pregnant women, Hofman and May say. The
women in the study, exercisers and non-exercisers, were not high risk.
For most healthy pregnant women, Hofman says, the research seems to support
exercising at least 30 minutes a day moderately, and probably more. Some
studies, he says, have demonstrated up to 60 minutes daily is generally