Practicing a sport for more than an hour a day may reduce breast cancer risk irrespective of age and weight, according to a recent study.

Research presented at the Ninth European Breast Cancer Conference shows that women with the highest level of physical activity reduced their risk of breast cancer by 12 percent compared least active women, according to a press release.

Physical activity is known to have a protective role in other cancers, as well as in disorders such as cardiovascular disease.

 "This is a low cost, simple strategy to reduce the risk of a disease that currently has a very high cost, both to healthcare systems and to patients and their families," Mathieu Boniol, research director at the International Prevention Research Institute in France, said in a statement.  "It is good news both for individuals and for policy makers."

For the study, researchers gathered data from a meta-analysis of 37 studies published between 1987 and 2013 that looked at the relationship between physical exercise and breast cancer risk. Although the results varied according to tumor type, the overall message was encouraging, researchers said.

They found that the results are largely independent of body mass index (BMI), so the effect must be due to more than weight control. And the age at which sporting activity starts also appears to be immaterial; the researchers found no indication that breast cancer risk would decrease only when physical activity started at a young age.

"Adding breast cancer, including its aggressive types, to the list of diseases that can be prevented by physical activity should encourage the development of cities that foster sport by becoming bike and walk-friendly, the creation of new sports facilities, and the promotion of exercise through education campaigns,"Boniol said. "This is a low cost, simple strategy to reduce the risk of a disease that currently has a very high cost, both to healthcare systems and to patients and their families. It is good news both for individuals and for policy makers."

Hilary Dobson, chair of EBCC-9's national organizing committee, said the findings are important for all women.

"This review seems to be telling us that the resultant improvements in breast health can now be added to the other established health benefits of physical activity," she said.