Tarheel Health Portal/Exercise's Effect on Breast Cancer
Breast cancer affects people from all walks of life; these effects are often negative. Reducing this negativity is important to many in society who have heard the heartbreaking news that cancer has taken over. Breast cancer is the second leading cause of cancer death, with lung cancer causing the largest amount of deaths due to cancer. One in eight women will develop breast cancer in her lifetime. Cancer is a term referencing the uncontrolled division of abnormal cells in the body. Upon continued growth, a tumor is formed by these cells. A patient does not get cured from cancer, but instead is said to be able to go into remission, a lack of cancer signs and symptoms. Upon going into remission, there is the possibility of relapse, which is the reappearance of cancer. Breast cancer is the occurrence of cancer in the breast. It is more prevalent in women than men. There are many treatments for cancer. Chemotherapy, radiation therapy, and surgical removal of the tumor are common treatments. Adjuvant therapy, is a secondary treatment that a patient also takes part in to increase the chances of survival. The medical community is beginning to look at exercise as a form of adjuvant care to better post-diagnosis outcomes. Moderate intensity cardio exercise, also known as aerobic exercise, seems to be the best exercise to increase these outcomes due to the biological factors it affects. Moderate intensity cardio exercise is defined as exercise that raises one's heart rate to between 50% and 70% of one's maximum heart rate. UNC has many different labs and research facilities that are looking into this relationship between exercise and cancer correlations to better improve the information that is known. Across the University of North Carolina at Chapel Hill campus, there are also various organizations that are involved with fundraising and increasing awareness of breast cancer. Some of these labs and organizations are listed below.
Known mainly for its association with diabetes, insulin can also have an effect on cancer. Insulin development is detrimental to cancer treatment when it is developed too rapidly. When the amount of insulin in the body increases, tumor growth is promoted. A lack of exercise is often associated with increased insulin development, therefore a more rapid growth of cancerous tumors. As one increases his or her amount of exercise, excess insulin in the body decreases. This decrease helps to slow down the growth of the tumor. Decreased insulin production was found to be the most prominent in women who lost 2kg of weight a year.
Inflammatory and Anti-Inflammatory Markers
Inflammatory and anti-inflammatory markers can have an effect on cancer. Inflammatory markers give rise to cancer because they prohibit normal cell growth and prompt cells to grow malignantly. Anti-inflammatory markers work to counteract this. During exercise, inflammatory markers are produced as stress is being put on the body, but the body also produces anti-inflammatory markers to oppose the ones that are produced. Exercise most often decreases inflammation because of the decrease in fat associated with exercise. As one loses weight, the amount of stress being put on the body during activity tends to decrease, causing less inflammatory markers to be released overall. Breast cancer is associated with chronic inflammation and exercise decreasing this is one association with decreasing tumor growth in a cancer patient.
Exercise also affects more day-to-day processes, such as blood circulation, ventilation and breathing, and improved bowel transit time.  Though these functions may not always seem necessary to consider when it comes to cancer, they can possess hold in cancer relations. The circulatory system can help transport nutrients and antibodies towards a cancerous tumor. An improvement of the circulatory system can better the circulation of blood, therefore nutrients, towards the tumor. This would possibly slow down tumor growth as antibodies arrive faster to fight off the mutant cells of the tumor. A better respiratory system will increase oxygen flow throughout the body, leading to an overall increase in bodily functions. A better bowel system that causes bowel movements to occur faster will likely lead to the body excreting toxins quicker. This means the toxins do not have as long of a time to be absorbed into the blood stream and cause possible harm. For people who are at a higher risk to gain weight, such as students entering into college, learning that exercise is beneficial to preventing breast cancer could turn out to be very beneficial.
Intensity of Cardio Exercise
It is still being disputed which type of cardio exercise is linked with more positive cancer outcomes. Typically, as one increases the dose (intensity in this aspect) of exercise, the risk seems to decrease lower and lower. This gives rise to a dose-response relationship between exercise and post-diagnosis outcomes of breast cancer patients. In fact, breast cancer has one of the most plausible dose-response relationships with exercise than any other cancer type. If more people knew that a little exercise could decrease chances of cancer, even by a small amount, more people may try to find a way to add exercise into their routine more often.
Little to No Exercise
It is widely known that someone who is sick should get rest. This is often taken way too far in terms of cancer patients. Cancer is not an overnight sickness that is easily combatted with rest. In one study, patients who took part in an exercise regimen were actually found to have a lower amount of fatigue then patients who did not do any measurable amount of moderate exercise. Other studies have looked at people who exercised upon diagnosis but then quit exercising after being diagnosed with breast cancer. A patient whose lifestyle followed this pattern typically had a four-fold increase in risk of death.
The most common forms of moderate-intensity exercise (raising one's heart rate to between 50% and 70% of one's maximum heart rate) in many of the studies conducted were fast walking, yoga, and bicycling. Comparing the people who took part in these exercises to the women who remained relatively inactive, there was a 33 to 88 ratio in the number of deaths, respectively. This is due in part to the adverse effect of increased insulin development and lower peak oxygen consumption.
Moderate-intensity exercise was also found to increase the overall QOL (quality-of-life) of patients. In Melinda Irwin's study, moderate cardiovascular exercise helped to decrease the symptoms of nausea, which is common amongst almost all cancer patients. Exercise also gives a patient a higher self-esteem, not only increasing their QOL, but creating motivation in a patient to continue on.
Too Much Vigorous Exercise
Though there is a dose-response relationship in cancer patients, it seems as though there is a threshold where the relationship ceases to exist. Vigorous exercise can be detrimental to one’s health. Vigorous exercise is related to higher fatigue, meaning that the body is being pushed close to its limits. This fatigue felt by the person means the body is working very hard and needs rest. A great amount of fatigue means that energy is likely not going towards fighting the cancer cells in the body, but going towards the exercise that the patient is taking part in.
Exercise and Different Treatments
Different cancer therapies have different effects on the body. This means exercise as an adjuvant care can work with each therapy in different ways, including the likelihood of following the exercise regimen. Moderate- intensity exercise has been shown to help not only reduce fatigue, but to also help increase tolerance of treatments for patients. But for some patients going through treatment, it is likely there will be days where exercise feels next to impossible, as cancer treatments can take a huge toll on patients.
If someone has a tumor surgically removed, it is not likely that patient is able to start exercising again the day of the surgery or even the upcoming days after the surgery. The patient will have to wait for the surgical incisions to heal and resting may be needed for it to heal. After everything heals, the patient will likely remain sore, reducing the likelihood of exercising.
Exercise is much different for patients going through chemotherapy or radiation therapy treatments. Chemotherapy and radiation take place across multiple trips and is not a one time process like many surgeries. Along with the biological mechanisms affected by exercise, exercise also has other positive effects on patients going through treatment. Participating in an aerobic exercise regimen increases the chemotherapy completion rate. Exercise is associated with an increase in tolerability for the patients, making it more likely that the patient will finish the regimen. This is likely due to the decrease in nausea symptoms that many patients going through chemotherapy and radiation have to face. On days of treatment, though, exercise is not recommended. The amount of stress put on the body by the treatments is too much for the body to withstand if the stress of exercise is added in. If both are done in the same day, the same thing occurs as when a patient participates in too much vigorous exercise; there is too much fatigue to fight off the disease.
On Campus Resources
For Grief and Support
Support Groups to Join This page includes various support groups for people with cancer or people going through grief.
UNC Counseling and Psychological Services UNC CAPS offers free psychological counseling to students who are experiencing grief. This could be for students who have recently been diagnosed with cancer or for students who know someone who has been diagnosed or has passed away from cancer.
Personal Training UNC offers personal trainers that can help create an exercise regimen to lead someone towards a healthy lifestyle and decrease the risk of cancer.
Well Woman's Visit UNC offers free clinical breast exams (as well as other exams) to female students.
Research Taking Place on Campus
Claudio Battaglini Claudio Battaglini is a member of the EXSS faculty at UNC whose research primarily deals with cancer and exercise.
Exercise Oncology Lab UNC has its own state-of-the-art oncology lab where research dealing solely with exercise and cancer takes place.
Specialized Program of Research Excellence (SPORE) in Breast Cancer UNC has one of only six SPORE programs in the nation.
External Resources and Further Readings
Franklin 5K Every year, the University of North Carolina at Chapel Hill chapter of Zeta Tau Alpha Sorority holds a 5K to raise money for breast cancer. The link leads to the Franklin 5K homepage where you can register or get more information about the run.
- http://link.springer.com/chapter/10.1007/978-1-4614-5647-6_1 Ma (2015). Breast Cancer Statistics
- http://www.cancer.org/cancer/breastcancer/detailedguide/breast-cancer-key-statistics American Cancer Society (2015). What are the key statistics about breast cancer? Accessed Date: April 20, 2015
- http://www.cdc.gov/physicalactivity/everyone/measuring/heartrate.html Division of Nutrition, Physical Activity and Obesity, National Center for Chronic Disease Prevention and Health Promotion (2011). Target Heart Rate and Estimated Maximum Heart Rate. Date Accessed: April 20, 2015.
- Nock NL and Berger NA. 2013. Exercise associated regulation of tumor promoters, hormones, and cytokines in cancer control. In: Ulrich, CM, Steindorf K, Berger NA, editors. Exercise, Energy Balance, and Cancer. 1st ed. Springer Science. p 21-36.
- Friedenreich C. 2011. Physical activity and breast cancer: Review of the epidemiologic evidence and biologic mechanisms. Senn H and Otto F, editors. Springer Berlin Heidelberg. 125 p.
- http://cebp.aacrjournals.org/content/18/1/11.short Neilson HK, Friedenreich CM, Brockton NT, Millikan RC. 2009. Physical activity and postmenopausal breast cancer: Proposed biologic mechanisms and areas for future research. Cancer Epidemiology Biomarkers & Prevention 18(1):11-27.
- http://europepmc.org/abstract/med/11427781 Thune I and Furberg AS. 2001. Physical activity and cancer risk: Dose-response and cancer, all sites and site-specific. Med Sci Sports Exerc 33(6 Suppl):S530,50; discussion S609-10.
- McTiernan A. 2008. Mechanisms linking physical activity with cancer. Nat Rev Cancer 8(3):205-11.
- Roberts CK and Barnard RJ. 2004. Effects of exercise and diet on chronic disease. J Appl Physiol 98(1):3-30.
- http://bjsm.bmj.com/content/42/8/636.short Friedenreich CM and Cust AE. 2008. Physical activity and breast cancer risk: Impact of timing, type and dose of activity and population subgroup effects. British Journal of Sports Medicine 42(8):636-47.
- http://www.cmaj.ca/content/175/1/34.short McNeely ML, Campbell KL, Rowe BH, Klassen TP, Mackey JR, Courneya KS. 2006. Effects of exercise on breast cancer patients and survivors: A systematic review and meta-analysis. Canadian Medical Association Journal 175(1):34-41.
- http://jco.ascopubs.org/content/26/24/3958.short Irwin ML, Smith AW, McTiernan A, Ballard-Barbash R, Cronin K, Gilliland FD, Baumgartner RN, Baumgartner KB, Bernstein L. 2008. Influence of pre- and postdiagnosis physical activity on mortality in breast cancer survivors: The health, eating, activity, and lifestyle study. J Clin Oncol 26(24):3958-64.
- Courneya KS, Segal RJ, Mackey JR, Gelmon K, Reid RD, Friedenreich CM, Ladha AB, Proulx C, Vallance JKH, Lane K, et al. 2007. Effects of aerobic and resistance exercise in breast cancer patients receiving adjuvant chemotherapy: A multicenter randomized controlled trial. Journal of Clinical Oncology 25(28):4396-404.
- Humpel N and Iverson D. 2005. Review and critique of the quality of exercise recommendations for cancer patients and survivors. Supportive Care in Cancer 13(7):493-502.