Breast cancer affects nearly 200,000 women every year, but studies show that you can protect yourself by upping your fitness level.

One study, by the World Cancer Research Fund and the American Institute for Cancer Research, found that exercising more, eating healthier and keeping weight in check could stop as many as 38 percent of breast cancer cases in America.

A more recent study, conducted by the journal Medicine & Science in Sports & Exercise, showed that even “moderately fit” women lowered their risk of developing breast cancer by one third. Women classified as “highly fit” reduced their risk of getting breast cancer by more than one half.
 
Researchers defined being “moderately fit” as doing an exercise like brisk walking for 2½ hours each week or vigorous aerobics, such as jogging, for 75 minutes weekly. Scientists said being “highly fit” meant doing twice that amount of exercise.

“Regular physical activity may be beneficial through several biological mechanisms,” said the journal’s study author Steven N. Blair, who is also a professor of exercise science at the University of South Carolina in Columbia.

These mechanisms include a cutback in hormone levels, improvements in insulin, less fat and better immunity, Blair explained.

In general, researchers agreed that a sedentary lifestyle is a risk factor for breast cancer and stressed that women stay active.

As a guideline, the American Cancer Society (ACS) recommends that women do at least 30 minutes (but preferably 45 to 60 minutes) of moderate to vigorous exercise five days or more each week.

Read Mana Lumumba-Kasongo’s tale of battling breast cancer here.