We already know that exercise helps reduce the risk of both heart disease and cancer. Now, a new study from Memorial Sloan Kettering shows that exercise can also help decrease the negative effects that cancer treatment can have on the heart.
The research, published in the Journal of Clinical Oncology, is the first to show that exercise reduces the heightened risk of cardiovascular disease in women with early-stage breast cancer.
“The fact that we now have a potential intervention that may help slow the accelerated risk [of heart disease] is, I think, incredibly important,” says study author Lee Jones.
Dr. Jones, an exercise scientist and Director of the Exercise-Oncology Research Program at MSK, along with colleagues at Kaiser Permanente in California, assessed exercise levels in approximately 3,000 women with early-stage breast cancer, then followed them for an average of nine years, looking at the incidence of heart failure and heart disease. They found that women who regularly exercised had a much lower risk of both of these conditions — and that the more they exercised, the lower their risk.
Some cancer drugs increase the risk of cardiovascular problems. Heart disease — an umbrella term that includes a number of issues like heart attack, stroke, and vascular disease — is a top killer of women with early-stage breast cancer, especially in those who are five years beyond their initial diagnosis.
“When women are diagnosed, they’re thinking about their breast cancer, which obviously makes sense,” says Dr. Jones. “But for a lot of those women, five years out, the risk of cardiovascular disease also becomes very important.”
How Much Exercise Is Enough to Reduce Heart Disease Risk?
Just how much exercise do women need to do to reap the benefits? It may be less than you think. Dr. Jones and team showed that even as little as 90 minutes per week can mitigate risk, regardless of age, weight, or cancer treatment.
Women who exercised 30 minutes a day, five days a week — the national recommendation for all Americans, with or without cancer — saw a 21% decrease in cardiovascular disease risk. Women who worked out for an hour a day, five days a week saw a 35% reduction. Even those who moved for a half hour a day, three days a week had a 10% reduction compared with women who weren’t active at all.
There’s no need to become a pro athlete overnight: The vast majority of women Dr. Jones studied cited walking as their primary source of exercise.
“The level we found to be protective wasn’t boot camp, wasn’t women running marathons, and wasn’t as high as some people might think,” he says. “I think people equate walking with low levels of physical activity, but that’s not right. The main message here is that more and more data are showing the increasing importance of exercise after a breast cancer diagnosis — a treatment that not only might help patients better tolerate their cancer treatments but also may reduce the long-term consequences of that treatment.”