Researchers at Brigham and Women’s Hospital (BWH) have found that regular physical activity, such as walking, can help reduce the risk of osteoporotic hip fracture in postmenopausal women. This is the latest finding of the landmark Nurses’ Health Study and was published in the Nov. 13 issue of the Journal of the American Medical Association.
“This study examined how the type and duration of walking, the most popular form of exercise among postmenopausal women, may benefit their bone health,” said Diane Feskanich, Sc.D., of BWH. “Our findings are encouraging, providing further evidence that women on the move have a significantly reduced risk of hip fracture. Given the fact that almost 30 percent of American adults engage in little or no exercise, we are hopeful this research will motivate more women to walk away their risk,” Feskanich added.
In the United States, one in every three adults 65 years old or older falls each year, with hip fractures resulting in the greatest number of deaths and most serious health problems. Women account for 80 percent of the 300,000 hip fractures that occur annually.
The study, which included investigators from the Harvard School of Public Health, showed that women who walked at least four hours per week had approximately a 40 percent reduction in the risk of hip fracture, compared with women who were mostly sedentary. Higher-impact exercise provided greater protection. Exercise equivalent to about three hours of jogging per week reduced risk of hip fracture by approximately 50 percent.
Additionally, researchers found that women who exercised regularly — equivalent to about one hour of walking daily or jogging for three hours per week — achieved the same protective benefits against hip fracture as provided by hormone replacement therapy (HRT). As many women reconsider HRT, this finding may offer an alternative to maintaining bone health.
While examining the different type, intensity, and frequency of exercise, the researchers were surprised to find that all levels of physical activity had a beneficial impact on reducing one’s risk of hip fracture. For every hour of walking added to a woman’s weekly exercise regimen, her risk of hip fracture was reduced by 6 percent. Activity was protective against hip fractures among both lean and heavy women.
Walking pace and amount of time spent standing were also significant predictors of hip fracture.
“The news about walking continues to be positive, and our study contributes further evidence that regular physical activity is a woman’s key to prevention of hip fractures,” said Feskanich. “To reduce risk, women should know that any amount of activity is better than none.”
These results were based on the analysis of questionnaires beginning in 1986 from more than 61,000 postmenopausal women, ranging in age from 40 to 77 years, participating in the BWH-based Nurses’ Health Study. During the 12-year follow-up, women were asked questions about walking time and pace, as well as the type and degree of other forms of exercise. Within this time span, 415 hip fractures were reported.