Cancer loves fat cells. So exercise can help prevent cancer, and we see the greatest impact of exercise on breast cancer.

"We don't exactly know all the reasons," said Dr. Anne McTiernan. "We think it relates to hormones in higher levels among people who are obese."

"And given the fact that there is a link between obesity and cancer risk, I am worried we are going to see a boomlet of cancer, years to decades down the line, in people who are overweight."

In an ongoing study at the Fred Hutchinson Cancer Prevention Clinic, researchers look specifically at the effects of exercise on breast cancer.

Women, such as 55-year-old Jane Quick, meet with a personal trainer for a 45-minute cardio workout.

Jane is typical of many women her age; women who have taken care of everyone else but themselves.

"I really need to make it work within my schedule. I work full time and I have kids. This has been very hard to do. And I can see why moms don't do it," she said.

But exercise is one of the best things a woman can do for her breasts. Dr. McTiernan has even written a book about the positive affects of exercise on breast health, particularly for post-menopausal women.

"Women still make estrogen after menopause. They just make it in their fat tissue. So women who have a lot of body fat tend to have high levels of estrogens and we know that those levels of estrogen predict risk of breast cancer," said Dr. McTiernan.

Exercise changes the body chemistry and cuts estrogen levels. Dr. McTiernan recommends a total of three to four hours of cardiovascular exercise per week.

"So it's about a half hour to 45 minutes a day … reduce the risk of breast cancer 30-40 percent," she said.

It's been almost a year, and Jane is finishing her volunteer participation in the study with a bang. She lost weight, furthered studies on cancer prevention, and learned how it's never too late to make changes.

"I feel I can do so much more,' she said. "I feel like I can join any gym and do anything that any 25-year-old can do with the equipment. After this I feel like, 'Bring it on. I can match anyone.'"

Physical activity, at any time, at any age, is a step in the right direction. Get started by building exercise into your day.

"Take the stairs instead of an elevator. …Instead of sitting down for coffee, take a walk. If you have to take your kids to a soccer game, you can walk around the soccer field instead of sitting and watching them. Any way you can build a little movement into your life is going to be a good way to get exercise," said Dr. McTiernan.

To step it up a notch, find a group or class you really like. Workouts offered throughout Western Washington vary from child's play to routines rated, "adults only."

For information about the NEW study, phone (206) 667-6444 or e-mail new@fhcrc.org