The lifestyles of soon-to-be mothers and fathers greatly impact the health of their children, at least in mice. In a new study published in the Journal of Applied Physiology, researchers at the University of Virginia found that mouse mothers and fathers who ate greasy foods in the days leading up to mating produced babies with much higher risks for metabolic problems later in life. But if the mothers stayed active during their pregnancies, those risks disappeared. It suggests, at least for mice, but maybe humans, when a mother exercises during pregnancy, she may help protect her unborn children against the unhealthy effects of the father’s poor eating habits, and hers as well. We need similar studies on human parents, but it seems plausible that continuing to be physically active during pregnancy can confer health benefits to the child, even much later in life.