WASHINGTON -- Researchers are trying to find out if exercise can really reduce a woman's risk of breast cancer.

There is some evidence that exercise not only reduces a woman's risk of developing breast cancer, but also may prevent the disease from coming back in breast cancer survivors.

At the National Cancer Institute, researchers are taking a new approach to see if exercise really makes a difference, reported WRC-TV in Washington, D.C.

Most of the previous studies on this subject have relied on people answering questions about how active they think they are, or were, before they got cancer. This study will follow some inactive women, ask them to get active and then really find out how it affects them over time.

"Our main thing that we are measuring is can we get you to do it, can you increase your exercise," said Dr. Jennifer Eng-Wong, the study's lead researcher. "That's what we really want to see. The other things we are going to look at are risk factors for breast cancers, things like circulating hormone levels in the blood, cholesterol levels and some immune markers."

The women in the study are between the ages of 18 and 75 and are either cancer survivors or at high risk for breast cancer. They must be considered sedentary before signing up.

Some participants then are asked to walk 10,000 steps each day, which is about five miles. They keep track of their steps with a pedometer.

"So, this is a nice way to do the intervention, really measure what they're doing, and see if it does have an effect," Eng-Wong said.

Volunteer and breast cancer survivor Kate Herrod keeps a busy schedule and sometimes finds it hard to reach her daily goal of 10,000 steps, but she has kept at it.

"Every time when I did this when I was tired and I didn't want to do it, it was like, I gotta get out there and do this for the women of America," she said.

Herrod got creative working all of those steps into her day. One night she did three miles walking around her living room while watching a movie.

• Special Section: Breast Cancer Awareness Month
• More Study Details: National Institutes of Health