About 14 percent of the fractures that occur among women in the U.S. each year are hip fractures. Mortality rates following a hip fracture can be as high as 20 percent. Being more physically active can reduce the risk of a hip fracture by 36 to 68 percent, according to a governmental Advisory Report.

Women’s Health Initiative (WHI) investigators looked at the association between the amount and intensity of physical activity and total and site-specific fracture risk. They also assessed fracture risk associated with sedentary behavior. “It really is the first large study of postmenopausal women that looked comprehensively at the association between physical activity and fracture risk,” Jean Wactawski-Wende, corresponding author on the study, told TheDoctor.

The more active women were overall, the lower their fracture risk.

The researchers analyzed data from 77,206 postmenopausal women between the ages of 50 and 79. Women reported how much time they spent being physically active and how much time they spent being sedentary. Physical activity was categorized as the amount of total activity, mild physical activity, moderate activity and vigorous activity. The average follow-up period was 14 years.

Participants’ total amount of physical activity was inversely associated with the risk of hip fracture: the more active women were overall, the lower their fracture risk. Walking for more than 10 minutes per day outside the home, doing yard work, and mild and moderate-to-vigorous activity were also associated with a lower risk of hip fracture.

Women who took part in moderate-to-vigorous physical activity did have a higher risk of wrist and forearm fractures, but these are not as dangerous as hip fractures. Sedentary behavior was associated with a greater risk of fractures of all kinds. “The big message here is that physical activity reduces fracture risk, even activities like walking, which are more common among women of this age group,” said Wactawski-Wende. So walking will benefit the heart and may also help the bones.

More attention to physical activity is important, Wactawski-Wende said. The WHI is a prospective study of postmenopausal women with an ongoing assessment of fractures. The researchers are hoping that when the WHI finishes in three years, they can confirm if physical activity will actually have a direct effect on fracture risk. “We are in the middle of an intervention now we will be able to report on in a few years,” said Wactawski-Wende. The researchers write that if the findings of the current study are confirmed, future recommendations for fracture prevention should promote at least light physical activity.

The study and a related editorial are published in JAMA Network Open.