Women's Health

Exercise and Breast Cancer in Women

exercise and breast cancer in women

Exercise and Breast Cancer in Women

The association between exercise and women with breast cancer has been well-known for some time: those who exercise do better during treatment. But now, we’re learning there’s a whole lot more to the story.


The rate of cancer cell growth and the risk for breast cancer itself both can be reduced through exercise. Even during short periods of strenuous or mild exercise, a hormone produced by the adrenal glands known as epinephrine is released. When we are under emotional or physical stress, this hormone plays an important role. Once the body signals the brain to produce and release it, the heart rate increases in order to send oxygenated blood to the muscles and brain for the required action. During regular exercise as well, the body releases epinephrine, according to research studies. This hormone is very important in activating NK cells, which attack foreign invaders in the body. When we exercise, these NK cells are released into the blood and make a significant contribution in curbing cancer cell growth.

The University of Copenhagen conducted a study on exercise and breast cancer. It was concluded that exercise could control tumor growth by increasing the NK cell infiltration. In the NK cell redistribution, exercise-induced muscle-derived IL-6 (a protein) was also involved. This protein is important for controlling metastasis, which is the growth of cancer cells. The Danish team imbedded human breast cancer cells into laboratory mice to study the effects of exercise on the cells’ growth. Blood serum samples were collected from both healthy women and those with breast cancer. The samples used for infused tumor cells were collected before and after exercise. They revealed the following information:

  • The growth ability of tumor cells was reduced in the mice and test tubes in the serum samples collected after exercise was completed.
  • Tumors developed in only 45 percent of the mice exposed to the post-exercise serum, while 90 percent of the mice that were not exposed to the serum experienced tumor growth.
  • Researchers observed a 50-percent reduction in the growth of cancer cells in the serum-treated mice.

The Danish study collaborates other research on the relationship between cancer cell growth and exercise. It was demonstrated that voluntary exercise could have a 60-percent reduction in incidences of tumors and growth. The American Cancer Society as well has stated that increased physical activity has been associated with a lower risk of breast cancer.

The rate of breast cancer diagnoses began to decrease in the year 2000; from 2002 to 2003 alone, the rate dropped by seven percent. One theory was that the decreased use of hormone replacement theory after the results of a women’s health initiative caused this decline. Statistics make clear that since 1989, the death rate for breast cancer has reduced, and larger decreases have been noticed in women under the age of 50. The leading cause of this could be advances in treatment, increased awareness, and early detection. Studies like this offer a brighter future for those with breast and other cancers.