Beth Shepard by Beth Shepard

breast cancer exerciseGet moving and stay moving — it’s been a consistent public health message for some time, with regards to preventing breast cancer and boosting overall well-being. Regular physical activity is an established strategy for reducing breast cancer risk.

Many studies found that the most physically active women were 25% less likely to develop breast cancer than the least-active women. More recent studies shed even more light on the importance of staying physically active — from younger adulthood through menopause and beyond — to ward off this deadly disease.

When it comes to breast cancer risk, fitness really does matter. In a large prospective study that evaluated cardiorespiratory fitness in women ages 20-83, women with the highest levels of fitness were 55% less likely to die of breast cancer — and those with the lowest fitness levels had the highest rate of age-adjusted breast cancer mortality. Women with a moderate level of fitness had a 33% lower risk of dying of breast cancer.

This result held up even after controlling for factors such as body mass index, smoking, drinking, contraceptive and estrogen use, and family history of breast cancer. Getting fit and staying fit is no guarantee that you won’t get breast cancer — but it does appear to decrease your risk in a big way.

Another study found that more is better in terms of exercise volume. Women with high amounts of total physical activity (1 hour a day of brisk walking) had a significantly lower risk of breast cancer compared to women with low amounts of activity (<1 hour/week). And here’s an interesting twist — inactive women who increased physical activity at menopause had a decreased risk of breast cancer compared to their peers who remained sedentary.

Two lessons here — moderate exercise, like brisk walking, may effectively reduce risk; and even if you’re not active now, it’s not too late to get moving and cut your risk of breast cancer.

Inflammation is thought to be a possible risk factor for cancer — one that may be modifiable with a long-term habit of regular exercise. The Alberta Physical Activity and Breast Cancer Prevention Trial found significantly less c-reactive protein (CRP) — a marker of inflammation — in active subjects compared to inactive controls. The effects were even greater for women with a high baseline level of physical fitness — but after adjusting for changes in dietary fiber intake, the differences were no longer significant. Researchers believe the difference in CRP was related to fat loss and concluded that while inflammation may be lowered with exercise, more research is needed. Other studies show both a positive and neutral effect of exercise on CRP. Considering the fact that exercise can help prevent weight gain, aid in weight loss, and prevent weight re-gain after weight loss, it could still be an important way to keep inflammation in check.

Preventing breast cancer is one of many excellent reasons to exercise that every woman should take very seriously. There are many risk factors we can’t change — like age, gender, genetics, and ethnicity — but committing ourselves to getting and staying physically active is something we all can do to reduce our risk of breast cancer in a powerful way.

Why not put on your walking shoes and give it a whirl today? Better yet, invite your best friend, grandmother, aunt, mom, sister, or teenage daughter to join you.


  1. Peel JB, Sui X, Adams S, Hebert J, Hardin J, Blair, S. A Prospective Study of Cardiorespiratory Fitness and Breast Cancer Mortality. Med Sci Sports Exerc 2009 Apr;41(4):742-8.
  2. Eliassen AH, Hankinson SE, Rosner B, Holmes MD, Willett WC. Arch Intern Med. 2010 Oct 25;170(19):1758-64.Physical activity and risk of breast cancer among postmenopausal women.
  3. Friedenreich C, Neilson HK, Woolcott CG, Wang Q, Stanczyk FZ, McTiernan A, Jones CA, Irwin ML, Yasui Y, Courneya KS. Alberta Physical Activity and Breast Cancer Prevention Trial: Inflammatory Marker Changes in a Year-long Exercise Intervention among Postmenopausal Women. Cancer Prev Res (Phila). 2011 Oct 7. [Epub ahead of print]