Evidence Says Exercise Lowers Your Risk Of Cancer

10/03/2017 11:29 GMT | Updated 11/03/2018 09:12 GMT

It's safe to say that society has accepted the body-mind-spirit connection, especially in times of stress and illness. Research is firmly behind the idea that one of the keys to all three is to take care of the first: the body. Scientists are now trying to determine specific ways that exercise improves the risks associated with cancer- before, during and after diagnosis.

Early first menses, late menopause, breast density, age at first childbirth, family history of the disease. There are so many risk factors for breast cancer that are out of our control. It feels like there's nothing much that women can do to avoid initial diagnosis or recurrence of the disease - that is not quite the case.

"There are things we can do every day to reduce the risk of breast cancer, to improve chances of not succumbing to breast cancer and to decrease the risk of recurrence," says Colleen Doyle, MS, RD, Director of Nutrition and Physical Activity at the American Cancer Society.

Ironically, one of the best things women can do to preserve their health goes against the wisdom of decades. For years, oncologists, surgeons, and other healthcare professionals have told women during and after cancer treatment to take it easy, rest, relax. Focus on getting well and catch up on your reading.

However, it turns out that one of the best ways to focus on getting well is to get up off that sofa and engage in regular physical activity.

Let's get physical - and statistical

People who exercise are less likely to get breast cancer than those who are less physically active, says Jennifer Ligibel, MD, medical oncologist at Boston's Dana Farber Cancer Institute. Specifically, women who are physically active on a regular basis are 25% - 30% less likely to be diagnosed with breast cancer, according to Ligibel.

A study at the German Cancer Research Center (Deutsches Krebsforschungazentrum) in Heidelberg, led by Drs. Karen Steindorf and Jenny Chang-Claude, found that there are some things women can do to lower their risk of breast cancer.

They also found that 19.4% of invasive post-menopausal breast cancers are attributed to hormone replacement therapy and 12.8% to a lack of physical activity. Combined, these two factors explain nearly a third of breast cancer cases, say the investigators. "That means that two factors, which each woman has in her own hands, are responsible for a similar number of post-menopausal breast cancer cases as the non-modifiable factors," notes Steindorf.

The challenge with these studies (and most others) is that they are observational; none are randomised, observes Ligibel. Thus, it is possible that women who are already in better health, who are eating better, and who are more conscientious about taking their medicines - may be the ones reporting their results to the researchers.

"We cannot prove a causal relationship based on these studies," says Ligibel, though there is clearly a relationship between physical activity and improved rates of survivorship."

The accumulated data are meaningful. In fact, Doyle notes that the American Cancer Society has been publishing articles about the importance of physical activity since the year 2000. "But now the data are strong enough to call our recommendations 'Guidelines,'" Doyle adds, which is a big step.

Of course, exercise is not completely protective, Ligibel notes. "Marathon runners get breast cancer, too," she says. But it can make a big difference - and it is one of the few concrete steps that women can take to improve their health.

Exercise is good for overall health, notes Doyle. It can improve cardiovascular fitness, muscle strength, bone health and body composition and can also play a role in weight loss, which has its own benefits. Regular physical activity can also improve the quality of life, by decreasing levels of stress, anxiety, depression and improving self-esteem. "It may seem counter-intuitive," says Doyle, "but exercise can also lessen fatigue."

"Regular physical activity is good for everyone," says Ligibel. "But there is good evidence that exercise is especially helpful for cancer survivors, especially breast, colon, and prostate cancer."

When to Start/What to Do

Exercise before treatment begins, during treatment, and after treatment are all linked to a decrease in recurrence.

Generally, moderate exercise translates into a twenty-minute mile, says Ligibel, though the precise definition may vary from study to study. "These women are not marathoners," she adds. "They spend three hours a week doing moderate walking." That's encouraging; exercise can help your life and prolong your life, but it needn't completely take over your life.

Moderate physical activities, per the American Cancer Society, are ones that you can perform while talking, but not while singing.

They include:

• Ice/roller skating

• Horseback Riding

• Yoga

• Downhill Skiing

• Golf

• Volleyball

• Baseball

• Badminton

• Brisk Walking

• Mowing The Lawn

• Raking and Trimming Shrubs

• Doing Housework

For further information and other studies like that mentioned above, visit