Aerobic Exercise Reduces Risk of Breast Cancer

Breast cancer is the diagnosis of 29% of all types of cancer in women in the United States. Unfortunately, it is also the leading cause of cancer death in women. In addition, the highest rates of breast cancer is found in the westernized world. Epidemiological studies point to causative factors such as western dietary patterns, decreased physical activity, rising obesity rates, and use of exogenous hormones (Stopeck & Thompson, 2013).

Other studies have shown that physical exercise can decrease the occurrence of breast cancer in postmenopausal women by up to 25%. In the same vein, obesity is a risk factor for the occurrence of breast cancer in postmenopausal women (Guinan et al., 2013). One epidemiological study showed that women who are involved in moderate to vigorous physical activity for 3-5 days a week can reduce their risk of breast cancer by 20-40% (Volaklis, Halle, & Tokmakidis, 2013).

Physical activity is related to breast cancer because it affects some biomarkers that result in the deadly disease. These include the insulin-glucose pathway, inflammatory biomarkers, and other anthropometric measurements. Physical activity is therefore a recommendation to decrease the risk of the occurrence of breast cancer.

A recent pilot study, which lasted for eight weeks, went further into the existing physical activity research by examining the effect of aerobic exercise on twenty-six breast cancer survivors. The study evaluated the effect of aerobic exercise on the following:

1. Waist circumference.
2. Blood pressure
3. High-density lipoprotein cholesterol.
4. Triglycerides.
5. Fasting glucose.
6. C-reactive protein (CRP) biomarkers.
7. Physical activity.
8. Body composition (bioimpedance analysis).

The first five listed items considered together are known as ‘metabolic syndrome.’

The participants were given polar heart rate monitors to check their compliance to the aerobic exercise schedules. They rotated between stationary bikes, treadmills, and rowing ergometers. The assessments were performed at the end of the eight weeks, and also three months post-intervention.

At the end of eight weeks, those who adhered to >90% of the exercise program showed a significant decrease in weight circumference. They also showed an increase in total weekly physical activity. These two factors are related to a decrease in the occurrence of breast cancer. However, since this was a pilot study, there is still a need for a longer trial with a greater number of participants.

In conclusion, aerobic exercise of 3 hours or more per week is now established as a secondary prevention method for breast cancer, especially in breast cancer survivors and postmenopausal women.

References:
Stopeck A. T., Thompson P. A. (2013). Breast cancer. Medscape reference. Available from http://emedicine.medscape.com/article/1947145-overview#a0101
Guinan, E., Hussey, J., Broderick, J. M., Lithander, F. E., O’Donnell, D., Kennedy, M. J., & Connolly, E. M. (2013). The effect of aerobic exercise on metabolic and inflammatory markers in breast cancer survivors-a pilot study. Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer, 21(7), 1983–92. doi:10.1007/s00520-013-1743-5
Volaklis, K. A., Halle, M., & Tokmakidis, S. P. (2013). Exercise in the prevention and rehabilitation of breast cancer. Wiener klinische Wochenschrift, 1–5. doi:10.1007/s00508-013-0365-8