Research has shown that exercise helps prevent breast cancer, but new studies are showing that it can also help alleviate treatment side effects.

According to the Centers for Disease Control and Prevention (CDC) and the National Cancer Institute (NCI), as of 2004, more than 20% of our nation’s 9.8 million cancer survivors are women who have lived through breast cancer treatment. As breast cancer detection and treatment methods continue to advance, more woman than ever are expected to survive the disease, but many will have to cope with treatment side effects and/or post-surgical physical limitations. While the benefits of exercise in preventing cancer are well established and frequently publicized, benefits in cancer survivors have not been as thoroughly studied and have even been debated. In some cases, certain side effects, such as the development of lymphedema, have been attributed to exercise following breast cancer treatment. Recently completed and ongoing clinical research now show that frequent moderate physical activity can help alleviate treatment side effects, improve quality of life, and possibly even prevent cancer recurrence in breast cancer survivors.

A Little Goes a Long Way
In May, The Journal of the American Medical Association published a landmark study suggesting that moderate exercise may reduce the risk of death from breast cancer in women already diagnosed with the disease.1 Physical activity levels were evaluated in approximately 3,000 women in the Nurses’ Health Study who had been diagnosed with stage 1, 2, or 3 breast cancer between 1984 and 1998 and were followed until death or June 2002. The primary measured outcome was breast cancer mortality risk according to the level of physical activity. “We assessed weekly leisure-time physical activity,” says Michelle D. Holmes, MD, DrPH, assistant professor of medicine at Harvard Medical School and Brigham & Women’s Hospital and lead researcher in the study. “We found that women who engaged in an amount of physical activity equivalent to walking one or more hours per week had better survival compared with those who exercised less than that or not at all.”

According to Holmes’s study, the maximum benefit occurred at the equivalent of walking three to five hours per week at an average pace, which was 2 to 2.9 miles per hour (20 to 30 minutes per mile). The benefit of decreased mortality from breast cancer did not increase with more vigorous exercise, which is an important finding, says Holmes. “Women do not have to run marathons for maximum benefits,” she emphasizes.

Working Past Treatment Woes
While decreased mortality from breast cancer is a landmark finding and the ultimate benefit of exercise for women diagnosed with breast cancer, it may not be tangible for women immersed in breast cancer treatment, dealing with the everyday stress and symptoms of the disease and the negative side effects of treatment. A diagnosis of breast cancer and its subsequent treatment wreak havoc on a woman’s physical and mental condition. Physical side effects of treatment include pain, fatigue, nausea, weakness, and difficulty sleeping. Psychological ramifications include depression, anxiety, stress, loss of sense of control, low self-esteem, and poor body image. Combined, these translate into a diminished quality of life, says Susan R. Harris, PhD, PT, professor at the School of Rehabilitation Sciences, Faculty of Medicine, University of British Columbia, and two-time breast cancer survivor. Harris says exercise during and after cancer treatment can help reduce side effects related to chemotherapy and radiation therapy, including fatigue, nausea, weight gain, and bone loss. “Women undergoing chemotherapy often gain weight, which can increase the risk of cancer recurrence. Steroids, radiation, and certain drugs can also cause premature menopause and bone loss. Aerobic and strength exercises can increase strength, minimize weight gain and bone loss, and improve overall physical functioning,” says Harris.

Joy Prouty, an American College of Sports Medicine-certified health and fitness director and Reebok Master Trainer, has codeveloped a practical video/DVD exercise program for breast cancer survivors with Josie Gardiner, another certified fitness professional, and Carolyn Kaelin, MD, MPH, FACS, director, Comprehensive Breast Health Center at Brigham and Women’s Hospital. Kaelin and Gardiner are both cancer survivors—Gardiner survived uterine cancer and Kaelin survived breast cancer. “My No. 1 choice for cardiovascular exercise is walking,” says Prouty, “because it is easy to do and can help control weight gain and bone loss related to chemotherapy.” Holmes also notes, “Walking was the most popular activity in our study group.”

Homework
Another recent study found that home-based physical activity positively improved overall mood and body image, and significantly reduced fatigue and increased energy in previously sedentary women diagnosed with early-stage breast cancer.2 The collaborative DVD created by Prouty, Gardiner, and Kaelin, was designed with home-based exercise in mind. Their DVD exercise program includes a basic strengthening program to improve muscular strength and flexibility affected by surgery. Breast cancer survivors start with slow resistance exercises without weights and then progress to exercises using 1-pound, 3-pound, and 5-pound weights. Other equipment, such as a stability ball and resistance tubing, are also used. “All the demonstrated exercises use equipment that is inexpensive and easily purchased to encourage women to exercise at home,” Prouty says.

Strength of Mind
In addition to the physical benefits, exercise can also help with psychological issues and quality of life for cancer patients. “Exercisers are less likely to feel depressed or distressed and have a better overall quality of life,” Harris says. “Physically active women with breast cancer have better mood, body image, and self-esteem,” Holmes adds.

According to Prouty, exercise is empowering for women with breast cancer. “Exercise gives them hope, a sense of control, and strength in their life after they have felt vulnerable from their disease for so long,” she says.

Certain types of exercise may promote psychological health benefits more than others. Dragon boat racing, a group sport growing in popularity worldwide, has attracted numerous breast cancer survivors because it combines athletic challenge, social interaction, and outdoor exercise. A dragon boat team consists of 20 to 22 women; since 1996, teams consisting solely of breast cancer survivors have provided social support and interaction for women with breast cancer. Harris was a member of the first breast cancer survivor dragon boat team in Vancouver, called Abreast in a Boat. The team has grown into a nonprofit organization raising breast cancer awareness and helping breast cancer survivors understand that they can live full and active lives despite the disease.

Exercise and Lymphedema
Her participation in dragon boat racing has led Harris to focus research efforts on exercise and lymphedema following breast cancer treatment with the hope of dispelling the myth that exercise actually causes upper extremity lymphedema. “Lymphedema, which is the swelling of an extremity after lymph node removal, occurs in 15% to 20% of women after breast cancer treatment,” notes Harris. Many women, including Harris herself, have been warned that vigorous, repetitive, and/or excessive upper body exercise can cause lymphedema. Several years ago, Harris participated in a study of the effects of dragon boat racing on breast cancer survivors and also published a series of case reports documenting that the vigorous paddling in dragon boat racing did not induce lymphedema in women who had undergone axillary lymph node dissection.3 A more recent study of dragon boat training also concluded that the sport increases upper body muscular strength in breast cancer survivors without causing lymphedema.4 “Some paddlers with pre-existing lymphedema have reported that exercise actually helps in reducing their arm discomfort,” Harris clarifies.

Practical Applications
How can breast cancer survivors practically apply all the research? While participants in Holmes’s study preferred moderate walking, other activities such as bicycling, swimming, gardening, and dancing are appropriate. “Any exercise that raises the heart rate and causes sweating works,” says Harris. For those who enjoy walking, she recommends that they time themselves for one lap or one mile around a track and then work toward completing a mile in 20 minutes. “This level of exercise is not beyond the reach of a breast cancer survivor,” she emphasized.

Breast cancer survivors also benefit from various strength-training exercises, as demonstrated on the DVD recently released by Prouty, Gardiner, and Kaelin. Prouty has years of experience tailoring exercise programs for breast cancer survivors based on the type of surgery they underwent. “Different types of breast cancer surgery affect different parts of the body,” she notes. Mastectomy, lymph node dissection, and reconstruction surgeries can impact range of motion, flexibility, and muscular strength and balance. For example, breast reconstruction surgery using transverse rectus abdominis myocutaneous (TRAM) flap affects the use of the abdominal and latissimus dorsi (back) muscles. Women who undergo TRAM surgery and other procedures may have serious movement limitations that can be improved with flexibility, strengthening, and balance exercises. “I look at how treatment creates imbalances in the body and then design exercises to help address those imbalances,” Prouty explains. She emphasizes, though, that all exercise should follow guidelines from the surgeon.

Studies are currently underway to compare different types of exercise following breast cancer treatment. California researchers are studying whether weight-bearing resistance exercise can reduce bone loss in women undergoing chemotherapy for invasive breast cancer. Harris and one of her graduate students recently received funding from the Canadian Breast Cancer Research Alliance to conduct the first study to examine the effects of practicing Pilates following breast cancer treatment. The study will evaluate whether exercises using the Pilates Reformer equipment can positively affect upper extremity function, range of motion in the shoulders, mood, and treatment-related pain. Other studies are continuing to examine the effects of exercise on immune response in breast cancer survivors.

Team Support
The study by Holmes, the Abreast in a Boat organization, and the breast cancer exercise DVD all encourage women with breast cancer to exercise appropriately during and after treatment. But, it has been reported that less than one-third of breast cancer survivors exercise at recommended activity levels.5 Although more and more physicians are prescribing exercise for cancer patients, being overwhelmed by the disease, self-consciousness, and depression may prevent breast cancer survivors from exercising. Participating in exercise with other survivors can help overcome these obstacles. According to the Abreast in a Boat Web site, dragon boating helps team members overcome the loneliness felt by cancer patients, regain control of their lives, create a support group for patients with cancer recurrence, and encourage survivors to share their experiences with others. When working with breast cancer survivors, Prouty uses the acronym HOPE (Help Other People Exercise) to promote the physical and psychological benefits of exercise. The psychosocial benefits of participating in a team sport, such as dragon boat racing, are especially rewarding. Harris was diagnosed with her second, more serious breast cancer just two years after Abreast in a Boat started. “Whereas I had no close friends with breast cancer during my initial diagnosis, I now had a support group of 23 incredibly crazy, irreverent, wonderful, loving women. They were all there for me—taking me to endless medical and surgical appointments, sitting with me through chemotherapy, sharing with me their own personal decisions about reconstruction, and continually making me laugh. We’ve often referred to ourselves as a ‘floating support group’ and this was certainly evident to me during my second go-round,” says Harris.

“Does exercise help breast cancer survivors? Absolutely,” Prouty says. She cites the example of a 40-year-old patient who had a single mastectomy with TRAM reconstruction, chemotherapy, and radiation therapy, and who began exercising after recovery from her surgery. “She started with simple range-of-motion exercises and walking,” Prouty says. One and one-half years later, she has full range of motion through her upper body, she works out at a gym on cardiovascular equipment, and does weight training on her own. “I hope the results of this study encourage breast cancer survivors to exercise,” says Holmes.

— Jennifer Sisk is a certified wellness educator/consultant with the American College of Wellness and a certified fitness instructor with the Aerobics and Fitness Association of America.

References
1. Holmes MD, Chen WY, Feskanich D, et al. Physical activity and survival after breast cancer diagnosis. JAMA. 2005;293(20):2479-2486.

2. Pinto BM, Frierson GM, Rabin C, et al. Home-based physical activity intervention for breast cancer patients. J Clin Oncol. 2005;23(15):3577-3587.

3. Harris SR, Niesen-Vertommen SL. Challenging the myth of exercise-induced lymphedema following breast cancer: A series of case reports. J Surg Oncol. 2000;74(2):95-98.

4. Lane K, Jespersen D, McKenzie DC. The effect of a whole body exercise programme and dragon boat training on arm volume and arm circumference in women treated for breast cancer. Eur J Cancer Care. 2005;14(4):353-358.

5. Irwin ML, McTiernan A, Bernstein L, et al. Physical activity levels among breast cancer survivors. Med Sci Sports Exerc. 2004;36:1484-1491.

Resources
The Breast Cancer Survivor’s Guide to Fitness DVD: www.brighamandwomens.org/healthinfo/breastcancersurvivorsguidetofitnessdvd.asp

Abreast in a Boat Web site: www.abreastinaboat.com

Dragon Boat Racing
Dragon boat racing originated in China more than 2,000 years ago and is rapidly growing in popularity worldwide as a competitive and recreational sport. The multicolored boats have a concave design that mimics that of ancient Chinese fishing vessels.

The boats are decorated with fierce dragon heads, scaly bodies, and elaborate tails. Each 18-meter-long boat—nearly the length of a large metro bus—holds 20 rowers who may paddle as fast as 70 to 80 strokes per minute and can travel over the water at 3 to 4 meters per second. The goal is to generate enough speed to cause the boat to rise high and smooth above the water by a cresting wave beneath the bow. A world-class-level dragon boat operating at top speed can actually pull up a water skier.

Dragon boat teams race on any smooth inland body of water in a straight lane. Each race ranges from 250 to 1,000 meters and is completed in three to six minutes. Over the last five years, dragon boat racing festivals, which include centuries-old rituals—such as a Taoist priest doting the eyes of the dragon head to bring the dragon out of its slumber—have popped up across the United States. Many dragon boat teams, like Abreast in a Boat, race for charity and do fundraising for festival races.

— Source: International Dragon Boat Association, www.edragons.org

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