When physically fit women exercise during pregnancy they could be setting their children up for better fitness too, say researchers, adding that regular workout during pregnancy may reduce obesity among offspring.
The study, published in the journal Science Advances, found exercise during pregnancy stimulates the production of brown adipose tissue, commonly known as brown fat, in a developing fetus.
Brown fat's primary role in the body is to burn off heat. It is often called good fat. White adipose tissue or white fat, on the other hand, is responsible for obesity and harder to burn off. It is commonly known as bad fat.
"Previous research has shown that exercise among overweight women during pregnancy protects against metabolic dysfunction and obesity in their offspring," said study researcher Min Du, professor at Washington State University in the US.
According to the researchers, the results show the offspring of physically fit mice that exercised daily during pregnancy not only had a greater proportion of brown fat relative to bodyweight but also burned white fat off quicker than the offspring of a control group of pregnant mice that did not exercise.
This helped prevent obesity and also improved metabolic health.
"This new study shows these benefits may also extend to the offspring of women who are healthy and in shape," Du said.
In the study, healthy maternal mice were assigned either to a sedentary lifestyle or to exercise daily. Their offspring were then subjected to a high energy/caloric diet.
Notably, female and male offspring from the experimental group whose mothers had exercised consumed more feed than offspring from the control group. Nonetheless, the experimental group mice showed less weight gain.
Additionally, there was an improvement in glucose tolerance in the female and male offspring from the experimental group. Glucose intolerance is a precursor to developing diabetes and other obesity-related diseases later in life.
Exercise during pregnancy also stimulated the production of apelin, an exercise-induced hormone, in both mothers and their fetuses. Apelin stimulates brown fat development and improves metabolic health.
The researchers also found administering apelin to the pregnant mice in the control group mimicked some of the beneficial effects of exercise on their offspring.
"This suggests that the apelinergic system could be a possible target for developing drugs that help prevent obesity," Du said.
The researchers hope their findings will encourage healthily and fit women to continue living an active lifestyle during pregnancy.