Exercise is linked with a lowered risk of breast cancer in African-American women, a new study finds. The study, which was recently published in Cancer Epidemiology, Biomarkers & Prevention, associates regular exercise, such as brisk walking, with a decreased risk of breast cancer.

Researchers from Boston University’s Slone Epidemiology Center discovered strong evidence tying physical exercise to a lower breast cancer rate in African American women. There has previously been little evidence for this group.

Researchers for the Black Women’s Health Study, a large study involving the health of black women, the researchers collected information regarding exercise habits, amount of time spent per week, and type of exercise being performed. The study involved over 44,000 African American women over a period of 16 years, and whether they developed breast cancer.

The researchers found that women who participated in vigorous exercise for at least seven hours each week were 25 percent less likely to develop breast cancer when compared to women who exercised less than an hour every week. Vigorous activity included running, basketball, swimming, and aerobics. Benefits were similar for women who walked briskly, but not for those who walked at a normal pace.

Lynn Rosenberg, ScD, professor of Epidemiology at Boston University School of Public Health and principal investigator of the Black Women’s Health Study, said in a statement, “Although expert review panels have accepted a link between physical exercise and breast cancer incidence, most study participants have been white women. This is the first large scale study to support that vigorous exercise may decrease incidence of breast cancer in African American women.”

According to cancer.org, approximately one in eight, or 12 percent, of women will develop invasive breast  cancer during their lifetime.