Engaging in regular vigorous physical activity before pregnancy reduces the risk of developing pregnancy-induced diabetes (a.k.a. Gestational diabetes), according to new research.

The Boston-based group led by Dr. Cuilin Zhang from the Harvard School of Public Health looked at the amount, type, and intensity of pre-conception physical activity in relation to Gestational diabetes risk in the ongoing Nurses’ Health Study II.

Among nearly 20,000 women in the study who delivered at least one infant between 1990 and 1998, a diagnosis of gestational diabetes was reported in 1192 women.

Analyses adjusted for age, family history of diabetes and dietary factors showed that both total and vigorous activity were significantly related to a lower risk of Gestational diabetes, the team reported at the American Diabetes Association’s annual meeting in San Diego.

“Compared with women who were sedentary both at an early age and before the index pregnancy, those who frequently engaged in vigorous activity in both periods had a 26% lower risk of gestational diabetes,” Zhang and colleagues found.

Among women who did not engage in vigorous physical activity, faster walking pace and more stair climbing also curbed the risk of gestational diabetes.

All in all, “regular physical activity is associated with lower gestational diabetes risk,” the team concludes.