Exercise as medicine for cancer: Q&A with Kerri Winters-Stone

Cancer patients don’t need to avoid physical exertion, including exercise – contrary to once widely held belief. Exercise is not only safe during and after cancer treatment, studies have found that physical training can bring improvements in daily functioning and quality of life while reducing symptoms such as cancer-related fatigue. And there is even some early evidence linking exercise to living longer with cancer.

The American College of Sports Medicine now has convened a roundtable of experts who are working on a major revision of the group’s exercise recommendations for cancer survivors issued in 2010. The goal is to translate the latest research into practical recommendations for healthcare providers, fitness professionals and cancer survivors.

Cancer Translated talked with roundtable participant Kerri Winters-Stone, Ph.D., about the prospects for using exercise to improve the care of people with cancer. Winters-Stone is co-leader of the Knight Cancer Institute’s Cancer Prevention and Control Program and holds the Elnora E. Thompson Distinguished Professorship in the OHSU School of Nursing. She recently received a $2.5 million grant from the National Cancer Institute to study the benefits of a partnered exercise program for couples coping with cancer.

CT: You’ve been researching the effects of exercise for people with cancer for some time now. What got you started?

Winters-Stone: It was purely by accident years ago. My research area was musculoskeletal health, osteoporosis and fall prevention when I connected with a nurse-scientist [Anna Schwartz, Ph.D., now at Northern Arizona University] in the OHSU School of Nursing who’d started doing some of the first work in using exercise for symptom management for people going through cancer treatment. She’d focused on reducing nausea and vomiting, anxiety and sleep disturbances but wanted to expand the scope to include body composition, bone health and functional performance because some of the newer cancer treatments were having adverse effects on those systems. That wasn’t her area of expertise. We started conversations and she offered me an opportunity to start collaborating.

CT: You’ve since led a number of randomized clinical trials of exercise, including one showing how targeted exercise helps men with prostate cancer. What all do we know about the benefits of exercise for people undergoing cancer treatment and in recovery?

W-S: The field of exercise oncology has made tremendous strides over the last 10 years, but frustratingly we don’t have enough of the right data to convince third party payers to reimburse for exercise for people with cancer. We have strong evidence to show that exercise can help patients manage their symptoms better. It may be able to reduce some of the side effects like deconditioning, losing your functional capacity and your strength and becoming really tired. We know that exercise can help prevent or mitigate those changes during treatment. And exercise after treatment can maybe reverse some of the more persistent side effects that remain after treatment. But we haven’t turned that into meaningful outcomes that would create the impetus for exercise to be the standard of care – and to be reimbursed by payers. We have a lot of professional guidelines. But they’re just recommendations. They are optional. It’s not like cardiac rehab where you come in with a heart attack and you get immediately put into an exercise rehabilitation program.

CT: That’s an eye-opening comparison. So why don’t cancer survivors have rehab?

W-S: The developers of cardiac rehab were able to show early on that exercise could reduce adverse outcomes and have an economic impact for hospitals. What they were able to show was that the incidence of a second heart attack was reduced in people who went through cardiac rehab. Cardiac events happen in a relatively short time so you can design a study to look at that. With cancer you don’t have a short-term event, or a biomarker or anything that is easily captured in a short period of time. So you may need to follow someone for 10 or 15 years until their cancer comes back or until they die in order to show that exercise may have delayed or slowed down the return of their cancer.

“At the very minimum, we know that cancer patients should continue to be as active as they can at all phases of treatment.”


Epidemiological studies have been able to show a link between higher levels of self-reported physical activity and lower risk of cancer recurrence, lower cancer-specific mortality, and lower all cause mortality. But we need evidence from interventional trials to show cause and effect. There are at least five ongoing trials now looking at whether exercise can prolong the lives of people with cancer. But results from those trials are five to ten years out.

CT: Until then, what are the prospects for establishing more structured exercise programs for people with cancer?

W-S: Not great. And I’ll tell you why: because of the costs. Most major cancer centers, small oncology clinics, and hospitals would probably agree that exercise could be helpful for patients. Is it helpful enough to pay for? There aren’t metrics available to show that there would be an economic benefit for putting patients into an exercise program. An alternative approach we’re hopeful about is to look at exercise as a practice to improve patient satisfaction with care. People want the means to take steps to restore their health. And patient satisfaction is a metric where you might be able to show justification for putting exercise into the care plan.

We are going to start adding a measure of the effect of exercise called “participation”, which addresses things like whether you are able to participate in work, in social activities, in leisure – things that have real context and meaning for patients. Others are looking at whether exercise enables people to complete more cycles of chemotherapy by reducing toxicity. That would bring more money for the hospital and be better for the patient because they get more lifesaving treatment.

CT: Is lack of reimbursement for exercise programs the only barrier?

W-S: We also need to give cancer care providers many more resources. As it stands, there is no real referral process for exercise. It would be easier for providers if they had a warm handoff to a fitness professional they could trust. And some providers hesitate to recommend exercise because they don’t know enough about it. At the roundtable we had a patient advocate, a triple cancer survivor who is only 62 years old, whose physician told her “to take it as easy as possible” and not exert herself. That message is still out there. At the very minimum, we know that cancer patients should continue to be as active as they can at all phases of treatment – before, during and after.

CT: What exactly are you tackling in the guideline development process?

W-S: It’s going to be a huge undertaking. The current guidelines were established in 2010. They provided levels of evidence for the benefits of exercise for people with cancer, as well as a lot of information about how to safely triage people into exercise programs and how to screen people for readiness to exercise. Cancer is complicated by the particular situations for every type of cancer; stem cell transplant is different from breast cancer is different from colon cancer. It’s more complicated than cardiac rehab. Part of what the roundtable will do is drill down and provide more prescriptive exercise programming, that is, programming that is more disease and outcome specific. For example, if you are concerned about excessive fatigue in your patient, what do you tell them to do? If you are concerned about excessive bone loss in your patient because she is going to go through premature menopause, what do you tell her to do?

CT: Getting people to stick with exercise isn’t always easy but compliance has been remarkably good in your clinical trials. How do you do it?

W-S: We definitely know some of the reasons for that. One of the best ways to promote subject compliance and retention in clinical trials is to get people exercising in a group with people like them. It becomes a social support network and it keeps people coming back. We also get  very good, well-trained instructors who have a lot of compassion for people who struggle with regular exercise. They know they are not training high-performance athletes. They are training people who may be overweight, in pain, and worried about how to exercise right and safely. They have a lot of compassion for all of those things, but also believe that everybody has potential to find an exercise program that works for them. And we know that other conditions have to be met. You can’t ask people to drive too far. You have to have options for people with widely different levels of ability. And it has to be paid for.

CT: In the future, how would you like things to change?

W-S: I would like to see medical systems get behind exercise as standard care. Getting this incorporated as a part of cancer therapy would change everything. That would create the demand for a whole system comparable to cardiac rehab but for people with cancer. It’s happening, slowly, but only on the backs of people who are very passionate about bringing those types of resources to patients through blood sweat and tears. And they are always at risk of losing funding. Exercise can actually be a relatively low cost investment with tremendous returns. We just need to convince the right people through our science and with meaningful and consistent data about exercise medicine.