PORTLAND,OregonAerobic exercise can sharply reduce the bone-wasting effects of chemotherapy, according to Anna L. Schwartz, PhD, associate professor and research scientist at the Oregon Health and Science University School of Nursing in Portland. Osteoporosis is becoming an increasingly common and troublesome side effect of chemotherapy, particularly in breast cancer, she reported. In addition to the treatment regimens, premature menopause and inactivity all contribute to a decline in bone mineral density (BMD). Aerobic exercise can reduce this decline and help prevent treatment-related weight gain while increasing muscle strength.
Exercise can thus play an important role in maintaining quality of life and functional capacity during and after cancer treatment, Dr. Schwartz said. She reported on a study that randomized newly diagnosed cancer patients to three groups: aerobic exercise, resistance exercise, and usual care. All of the patients were women and they were also randomized by menopausal status. Persons with metastases, psychiatric disorders, endometrial disease, and diabetes were excluded.
The three groups had substantially similar demographics and range of treatments, Dr. Schwartz said. At the outset, the researchers evaluated each subject’s body composition, the bone mineral density of the lumbar spine, and muscle strength measured by 1-repetition maximum tests, and functional ability measured by a 12-minute walk.
Both exercise groups were asked to engage in vigorous physical activity at home for 15 to 20 minutes at least 4 days each week. Members of the aerobic group could choose an exercise that that they enjoyed, for example, walking, dancing, bicycling, or swimming. Resistance group members did a program of exercises using TheraBands, Dr. Schwartz said.
The usual care group got no special guidance on exercise. Some of its members began exercising on their own, but most stopped within 1 or 2 weeks. All subjects underwent the walk test 3 and 6 months into the study and had body composition and lumbar spine evaluations at 6 months.
Exercisers Got Much Stronger