A morning jog, fast walking, weightlifting and other forms of exercise were off-limits for most cancer patients as recently as 15 years ago.
Fast forward to today, and the latest research suggests that exercise is not only safe for many people with cancer, but might relieve the side effects of cancer treatments—and might even improve survival.
Researcher Karen Mustian, a University of Rochester Medical Center exercise psychologist and physiologist specializing in cancer, designs and studies exercise programs specifically for patients and survivors.
We spoke with her about the evolving story of exercise and cancer.
Scripts: How has the view of exercise for cancer patients changed?
Mustian: It was not that long ago that we were very hesitant to promote exercise for people with cancer, particularly those receiving treatments. We worried they were too sick to work out, and that exercise somehow would make them worse and compromise their ability to complete their treatments and recover.
By 1999, however, almost a dozen small studies suggested exercise might be safe and helpful for cancer patients. Since then, there’s been a dramatic increase in scientific evidence supporting exercise, ranging from simple walking, weightlifting, Tai Chi, yoga and even activities as vigorous as team paddling or dragon boat racing.
Scripts: So, given the changes in thinking, how much exercise do you recommend?
Mustian: Studies have shown exercise to be helpful for a wide variety of debilitating problems. It can improve cancer-related fatigue, sleep problems, depression, anxiety, physical function, immune function and overall quality of life. Experts now suggest that cancer patients and survivors should strive to reach the recommended public health guidelines for physical activity – either moderate-intensity aerobic activity for a minimum of 30 minutes, five days a week, or vigorous-intensity aerobic activity for a minimum of 20 minutes, three days a week.
But the story is not completely done. Some people treated for cancer will need exercise programs that are modified to ensure safety and effectiveness without making cancer-related side effects or other health conditions worse. At this point, scientific evidence does not provide the detailed knowledge to allow us to write explicit exercise “prescriptions” with precise doses, modified for specific cancer-related side effects. Still, we can make broad recommendations.
Scripts: What do you advise for your patients?
Mustian: First, I ask them what they like to do. Do they prefer to be inside or outside? If they like the outdoors, I encourage them to find a physical activity they can do in each season. In Rochester, even in the winter, this might mean cross-country skiing or simply getting outside and playing in the snow. It’s really important to find something you like to do.
I also suggest they work with an exercise professional who has additional training in the unique needs of people treated for cancer. I also encourage them to speak with their oncologist and ask if there are special limitations that they need to consider.
Some cancer patients come through my lab, asking about the amount of exercise they have to do to get rid of their fatigue. Unfortunately, there is no “dose” of exercise specifically designed to reduce fatigue. So, my staff tailors the exercise prescription to each individual, taking into account the baseline level of physical fitness, unique limitations and preferences, along with their goals and whether they’re interested in achieving improvements in mental health, physical health, or some combination.
It’s important to give people a range of options. Cancer patients and survivors have a lot of obligations to manage — jobs, family, and treatments. Asking them simply to add 30 minutes of exercise a day is not always practical or even necessary to achieve significant reductions in cancer-related side effects. For instance, if one person’s main goal is to lift depression or anxiety or fatigue, and they might be able to achieve that with as little as 10 minutes of exercise a day.
Scripts: Do we know exactly how exercise helps cancer patients?
Mustian: It is difficult to say. To begin with, we don’t know precisely what causes the many side effects of cancer in the first place. We know cancer-related fatigue, neuropathies and cognitive impairments are real, but we can’t articulate a specific cause. We think they are linked to the disease and treatments. We also can’t describe exactly how exercise — either through biological or psychological mechanisms — alleviates these side effects.
It is likely exercise works because it’s what we call a “multi-targeted, multi- system” intervention. Just think: When you do something simple, like standing up from your chair and walking across the room, you activate your entire body from the cellular to the whole organ level, triggering multiple systems, including your muscles, heart, lungs, brain, immune system and more.
Scripts: Your research has shown that yoga can improve sleep and quality of life for cancer survivors. Is that the best exercise?
Mustian: Yoga is a wonderful exercise, but it’s not for everyone. Some people simply don’t enjoy it. For those who do, it helps to reduce several side effects associated with cancer and its treatments. Remember, while some yoga is “gentle,” that does not mean it is easy.
My study and others have shown that yoga works best for cancer patients when it integrates breathing exercises, mindfulness and meditative exercises, and imagery components with yoga postures. Collectively, those components seem to make yoga enjoyable. They’re also what probably make yoga successful.
Again, the people I see in my research studies are interested in living longer, but they also emphasize they want their quality of life to be high. They are not so much looking to exercise to gain extra years, even though they suspect it may help with this, but they are interested in using it to help them maintain their functional independence so they can participate fully in all they want to do. I think that is what most of us, even those of us lucky enough not to have experienced cancer, want for ourselves.
Karen Mustian directs the Physical Exercise Activity Kinesiology Clinical Research Core Laboratory, or PEAK Lab, at the Medical Center. For more information or to contact her, call 585-273-1796 or visit: http://www.urmc.rochester.edu/physiology-exercise-lab/index.cfm