One in eight women in the United States will develop breast cancer; the United States has the highest incidences of breast cancer in the world. Breast cancer is the second most common cause of cancer in women after skin cancer, and second to lung cancer as the most common cause of cancer-related death.
The American Cancer Society recommends regular physical activity and a healthy diet to prevent cancer (Kushi, Byers et al. 2006). Research suggests that regular exercise may decrease breast cancer risk (McTiernan, Kooperberg et al. 2003; Eliassen, Hankinson et al. 2010), particularly when performed at a moderate intensity level (Friedenreich, Courneya et al. 2001).
Breast cancer is identified by different stages, indicating progression of the disease. These stages are associated with different survival rates as well. Below are estimated survival rates for different stages of breast cancer, according to www.cancer.org (2010). Survival rates are based on the percentage of individuals living five or more years after diagnosis.
Traditional viewpoints that suggested breast cancer survivors avoid exercise (particularly resistance training) are now being challenged with research. These intervention studies usually involve aerobic exercise such as a walking program to maintain cardiovascular fitness and to improve body composition. Breast cancer survivors, particularly premenopausal women, often experience weight gain after chemotherapy. This weight gain has been associated with an increased recurrence and death from breast cancer (Chlebowski, Blackburn et al. 2006). Weight-bearing exercises such as walking and tai chi also have a positive effect among breast cancer survivors by reducing bone loss (Schwartz, Winters-Stone et al. 2007; Peppone, Mustian et al. 2010). Adding walking poles to a walking program also improves upper body muscular endurance in breast cancer survivors (Sprod, Drum et al. 2005).
Exercise is an important component of treatment for breast cancer patients. Whether performed during treatment or after treatment, patients can benefit with improvements in fitness and quality of life. Combining cardiovascular and resistance training seems to have the most benefit, particularly in patients undergoing chemotherapy, radiation, and surgery.