Australasian Science: Australia's authority on science since 1938

Maternal Exercise Keeps Unborn Boys Trim and Terrific

A study published in PLOS ONE has found that male offspring benefit more than females from the positive effects of exercise during pregnancy.

A University of NSW team led by Prof Margaret Morris examined whether the detrimental effects of maternal obesity on offspring could be reduced by the mother’s voluntary exercise prior to and during pregnancy. “We hypothesised that voluntary exercise during pregnancy would have beneficial effects on glucose levels and metabolism,” Morris said.

Female rats were fed a high-fat diet, including pies, cakes, dim sims and biscuits, for 6 weeks before mating and throughout gestation and lactation. Half underwent voluntary exercise from 10 days prior to mating until their offspring were delivered, while others remained sedentary. The expression of genes related to glucose, metabolism and inflammation in fat and muscle tissue were then measured 19 days after birth.

“Maternal exercise appeared to decrease the metabolic risk induced by maternal obesity, limiting fat deposits around the abdomen in the offspring and improving their insulin and glucose metabolism during the lactation window,” Morris said.

The effects were sex-specific, with males appearing to benefit more from maternal exercise than females. “Maternal exercise significantly improved male offspring’s insulin and glucose metabolism whereas female offspring showed only modest improvements,” Morris said. “As to why male offspring seem to benefit more than females from the positive effects of exercise during pregnancy, that’s a mystery that we hope to solve with further research.

“While this study was conducted in rats, the findings are a useful addition to the existing body of evidence that points to the importance of both diet and exercise for pregnant women to ensure the future health of their baby.”