According to a press release published by EurekAlert, new research described in the journal Cancer Epidemiology, Biomarkers & Prevention reveals that postmenopausal women who are very active or walk at least seven hours a week have a reduced risk for breast cancer.

Women who did at least an hour of vigorous physical activity every day showed a 25 percent lower risk for breast cancer. Those who walked for at least seven hours a week had a 14 percent lower risk for breast cancer. The study included 73,615 postmenopausal women.

“We examined whether recreational physical activity, specifically walking, was associated with lower breast cancer risk. Given that more than 60 percent of women report some daily walking, promoting walking as a healthy leisure-time activity could be an effective strategy for increasing physical activity among postmenopausal women,” said Alpa Patel, Ph.D., senior epidemiologist at the American Cancer Society (ACS) in Atlanta, Ga. “We were pleased to find that without any other recreational activity, just walking an average of one hour per day was associated with lower risk of breast cancer in these women.”

Researchers determined that the observed benefits of physical activity and walking were not influenced by body type or hormonal status, even after making adjustments.

“Current guidelines recommend that adults should strive to get at least 2.5 hours per week of moderate-intensity activity, or 75 minutes per week of vigorous-intensity aerobic activity for overall health. Higher levels of activity may provide greater benefit for breast cancer prevention,” said Patel.

The researchers identified 73,615 postmenopausal women from a cohort of 97,785 women between the ages of 50 and 74, recruited between 1992 and 1993 to the Cancer Prevention Study II Nutrition Cohort. Participants completed a self-administered questionnaire on demographic, medical, and environmental factors during their enrollment process. They also completed follow-up questionnaires every two years between 1997 and 2009.

Every participant provided information on the average number of hours they spent on various physical activities including walking, jogging, swimming, playing tennis, bicycling, and performing aerobic exercises every week and the number of hours spent doing things like sitting, including watching television and reading.

Among all of the study participants, 4,760 individuals developed breast cancer.