stanford medicine


Rxercise get plenty of rest?

Special Report


Get plenty of rest?
That’s so retro

For Anabel Stenzel (L) and Isabel Stenzel Byrnes, living with cystic fibrosis and a lung transplant (or two) is no excuse to take it easy. In fact, the twins believe exercise will help extend their lives.

In 1966, Walter Bortz, MD, was downhill skiing with his family in Stowe, Vt. — “absent-mindedly tooling along,” he recalls — when one of his ski tips stuck in the snow and he fell, tearing his right Achilles tendon. After surgery, doctors put a cast on his leg. Six weeks later, the cast came off, but his leg looked as though it had aged 40 years.

“It was purple, weak and withered,” he says.

Bortz, now an adjunct clinical associate professor emeritus of medicine at the Stanford School of Medicine, speculates that the surgery was not to blame for the decrepit state of his limb. The problem, he believes, was that he had not used it for a month and a half. A search of the medical literature supported this hypothesis: Immobility appeared to produce the same effects on the body as aging.

Bortz later coined the term “disuse syndrome” to describe the profusion of physiological changes — cardiovascular vulnerability, musculoskeletal fragility, immunologic susceptibility, premature aging and frailty, among others — that occur when someone is in a state of forced inactivity, such as prolonged bed rest. “The lesson is, ‘Use it or lose it,’” he says.

Of course, it’s not as though people have only recently discovered the benefits of exercise. “Lack of activity destroys the good condition of every human being, while movement and methodical physical exercise save it and preserve it,” Plato observed more than 2,300 years ago.

Slower to take hold, however, has been the evidence that exercise can help people recover from illnesses and injuries. “The science on this is solid, but it is still not well-recognized in medicine,” Bortz says. “What I learned in medical school — that if it hurts, lie down — still largely rules.”

The familiar doctor’s advice to rest and get plenty of fluids still makes sense for many short-term injuries and illnesses. But bed rest for more than a few weeks? Not so much — even for transplant recipients, kidney failure patients and cancer survivors. Bed rest, as well as just general inactivity, is being challenged as study after study shows that it is often counterproductive to the healing process, prolonging the time to recovery and increasing the risk of other complications.

“There’s practically nothing that exercise isn’t good for,” says Michael Fredericson, MD, director of the Physical Medicine & Rehabilitation Sports Medicine Clinic at Stanford and a professor of orthopaedic surgery. “It helps with every single health parameter, from lowering cholesterol to improving heart function and preventing atherosclerosis, obesity and Alzheimer’s.”

The past few decades have brought a boom in research on the health benefits of exercise, including its role in recovery. How does it help? At the cellular level, exercise, especially weight training, first actually damages muscle fibers, causing satellite cells — a type of progenitor cell, like a stem cell — to proliferate and form myoblasts that fuse to the site of the damage. The myoblasts donate their nuclei to the muscle cells, each of which can hold lots of nuclei, allowing the cells to synthesize more protein and grow bigger. Thus, muscles grow stronger. Similarly, aerobic exercise strengthens the heart muscle, improving its pumping efficiency. It also increases the number of red blood cells in the body and fuels the growth of microvascular networks in muscle tissue, all of which increase endurance. Exercise also boosts collagen synthesis to strengthen ligaments and tendons, and it releases neurotransmitters and endorphins to fight depression and anxiety.

On the flip side, the negative effects of inactivity have been thoroughly cataloged, perhaps nowhere more starkly than in a famous 1966 study in which researchers recruited five 20-year-old men to spend nearly three weeks in bed. Of course, the men’s heart health declined; what was surprising was how much. By the 20th day in bed, their cardiac output, the amount of blood pumped each minute by the heart, had dropped 15 percent. Their bodies’ ability to transport and use oxygen during exercise — a common measure of physical fitness — had fallen nearly 28 percent. A 30-year follow-up study concluded that the 20 days the young men spent in bed “had a more profound impact on physical work capacity than did three decades of aging.” Yet these men were all able to regain — and in some cases exceed — their initial aerobic strength after an eight-week training program.

Fredericson cautions, though, that exercise is no panacea and that not all types are good medicine. Seriously ill individuals should get the go-ahead from their doctor before launching a regimen. Some people really are simply too sick to exercise. But that’s not as common a scenario as you might think.

Had Bortz injured his leg in 1990 as opposed to a quarter of a century earlier, he likely would have benefited from a growing trend in medicine called accelerated rehabilitation, a clear corollary to the use-it-or-lose-it school of thought. This concept began to gain ground in the late 1980s after doctors observed that patients recovering from muscle and ligament injuries, or surgical repairs to those injuries, fared better the sooner they started exercising the afflicted body part. For example, orthopedic surgeons found that patients recovering from the surgical reconstruction of their anterior cruciate ligaments who neglected doctors’ orders — that is, they put weight on their knees and moved them around more than they were supposed to — “regained strength much faster and performed better and with more confidence in the later stages of rehabilitation” than those who adhered to the prescribed rehabilitation protocol, according to a 1992 study in the Journal of Orthopaedic & Sports Physical Therapy.

The same study found significantly better outcomes among patients who followed a more intense rehabilitation regime — one that had them putting weight on their leg and performing range-of-motion exercises just two to three days following surgery. Recently, a Wall Street Journal article focused on how doctors are increasingly prescribing exercise for patients suffering from osteoarthritis, a degenerative joint disease, as opposed to the traditional advice of taking it easy to protect the joints.

In many cases, exercise cannot specifically target an injury or disorder (think of kidney disease or cancer). But it can improve a patient’s functional capacity — that is, the ability to do everyday kinds of work, from picking up a dropped pen to carrying a box of books up a flight of stairs.

Improving dialysis patients’ functional capacity is often overlooked, says Patricia Painter, PhD, an expert on kidney patients’ physical function and an associate professor of nursing at the University of Minnesota. Painter, a former Stanford research scientist, says nephrology has been slow to promote exercise. “It’s frustrating. There’s plenty of research that says exercise is good for patients with kidney disease and on dialysis. But nothing is being done about it,” she says. “Most nephrologists are not pushing exercise. Medicare covers dialysis but not exercise.”

Among patients ages 40 to 50 on dialysis, close to half are classified as frail, she says. “They’re basically functioning like very old people, and that can be prevented and corrected with exercise,” she says. “What’s the point of going through all this dialysis treatment if you can’t do things for yourself? If your quality of life is going to be so poor?”

“We were always told that you have to exert twice the effort for half the reward,” says Anabel Stenzel, 39, who received lung transplants in 2004 and again 2007, as she walks to and fro, hands on her head, warming down after a 100-meter sprint on Stanford’s Cobb Track. Organ recipients have to work harder than people in the general population to gain muscle and the aerobic benefits of exercise because the steroids, immunosuppressants and other drugs they take impair muscle and bone health.

Photography by Ruthann Richter
Running for their lives and for the fun of it at the weekly transplant boot camp at Stanfordís Cobb Track.

Stenzel and her identical twin sister, Isabel Stenzel Byrnes, who received a lung transplant in 2004, both have cystic fibrosis. Inspired by workouts they attended while training for the 2008 U.S. Transplant Games, they started the Transplant Boot Camp, a weekly workout for organ recipients at Stanford.

“It’s really about camaraderie,” Anabel Stenzel says. “There are people who join us with only 45 or 55 percent lung capacity, and they can do only so much. But we’re all in this together. We’re here to do our best.”

A 2010 literature review in the Journal of Heart and Lung Transplantation found evidence that exercise improves skeletal muscle strength and lumbar bone mineral density, as well as functional capacity, among lung-transplant patients.

Stenzel believes exercise can extend transplant patients’ lives. “Everyone I know who has lived 10 years post-transplant is an active exerciser,” she says. “It improves well-being, but maybe more importantly helps decrease the side effects of the medication. I believe exercise is as important as immunosuppression and is not stressed enough by transplant doctors.”

Patients fighting cancer also face serious side effects, including weakened muscle, bone and immune function, from the powerful drugs they take to treat the disease. In addition, the drugs cause nausea and overall physical and mental fatigue. It’s hard enough to motivate people to go to the gym when they are not dealing with such discomfort and pain, says Joyce Hanna, MA, MS, associate director of the Stanford Health Improvement Program. She has tackled this head on with a program called Living Strong Living Well. It invites adult cancer patients to participate in a free, 12-week exercise program now running at many YMCAs. Classes include weight and cardiovascular training and take place twice weekly for 85 minutes.

Instructors urge participants to show up regularly — even if that means just making it through the door of the gym. Says Hanna, “When I give them a presentation on the first day, I say, ‘You’re going to wake up one day and not want to come. I can promise you that. You’re just not going to feel like it. But we want you to come anyway, and we’ll just adapt the program for you.’”

Research shows that physical activity helps counteract the effects of chemotherapy and improve overall quality of life among cancer patients. Exercise also has been shown to help fight the depression and anxiety cancer patients can feel as a result of the disease and arduous treatment regimen. Other research suggests that exercise may actually decrease the recurrence of certain types of cancers and increase the longevity of cancer patients.

A little more than a decade ago, however, advising cancer patients to exercise would have raised eyebrows.

“People in the health field were saying you should not exercise cancer patients,” Hanna says. “They felt that since cancer wore down the immune system, exercise would wear it down even more. They also questioned why you would exercise someone who was already fatigued. Wouldn’t that make them even more fatigued? But this was kind of a myth. Now research suggests that moderate exercise, not rest — with some exceptions, of course — is just what cancer patients need.” 

On a Wednesday last March at the El Camino YMCA in Mountain View, Calif., a half-dozen women were led through a series of stretches by Julie Grosvenor, the Y’s Active Older Adults Program coordinator. “The first couple of weeks I think are the hardest,” Grosvenor says of the program. “Some patients are feeling scared about what they’ve gone through, and they’re all feeling pretty weak because of chemo.”

One participant, Laura Toby, 55, says that she had always done aerobic exercise. But treatment for multiple myeloma took a big toll on her muscles. “After I got a stem cell transplant, my whole body just went thbffffft,” she says, making a deflating sound. “So I was really interested in lifting weights and having someone work with me, and this program has been great for that. I always seem to injure myself when I try to do weights on my own. I definitely feel now that I’ve got better body toning.”

Another participant, Emily Williams, 61, says she, too, has always been an avid exerciser. She is living with terminal ovarian cancer. “Working out is always something I’ve enjoyed. But for the last two years that I’ve been going through chemotherapy, I’ve also realized that it gives me some control over what’s happening to me,” she says. “Not only do I feel better physically, but I don’t feel as much under the control of my cancer and all the stuff that surrounds it — all the blood tests and infusions. Taking this class has given me a lot of confidence to continue. So I guess not only has it been physically good, it’s been emotionally good for me. It’s the highlight of my week.”


E-mail John Sanford

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Here's help

American College of Sports Medicine

offers exercise guides for a wide range of health conditions.

Living Strong Living Well

is an exercise program for cancer patients and survivors.

U.S. Department of Health and Human Services

has physical activity guidelines, sample exercises and tips to get moving:
(800) 336-4797






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