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Running head: EXERCISE AND BREAST CANCER
The Correlation between Exercise and Breast Cancer
Jana De Vries
Ferris State University
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Abstract
There is no doubt, in this day and age, that exercise belongs between the most important factors
of remaining healthy and achieving longevity. Engaging in physical activity enables us to stay
strong, contributes to our independence and creates a state of well-being. Additionally, it helps
us to prevent or possibly postpone diseases and certain conditions. It has been proven, by many
studies and researches, that any type of physical activity is beneficial and can have a very
positive impact on our health status. Most importantly, exercise improves chances of our medical
outcomes. This is especially true in the female and breast cancer cases. This manuscript
examines and analyzes studies which were conducted to research the link between physical
activity and breast cancer. Furthermore, it explores physical activity as a way to prevention of
breast cancer, and as an important part of supportive/ adjunctive therapy during treatment and
after surviving this disease. All studies presented are compared, explored, and suggestions are
made for a future research.
Keywords: Breast cancer, exercise, prevention, treatment, adjunctive therapy, studies
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The Correlation between Exercise and Breast Cancer
How does exercise affects prevention, treatment, and post-treatment (survivorship) of
breast cancer? What is the correlation? Most of the research presented in this literature review
attempted to answer these above stated questions.
Breast cancer is the most common type of the cancer diagnosed among women. As
recent studies suggested there is quite significant correlation between exercise and breast cancer.
Furthermore, “The American Cancer Society assumes that around one-third of the yearly
500,000 malignant tumor-related deaths result from inactivity, high caloric intake, and
overweight” (Graff & Wessely, 2010). Engaging in physical activity decreases the risk of the
breast cancer and is recommended while undergoing cancer treatments to positively influence the
outcomes of the treatment regimen. Furthermore, it is a great adjunctive therapy for breast cancer
survivors that helps them with improvement of quality of life and get their strength back.
However, “the question still remains unanswered which kind of activity in daily routine, in
professional life, and in leisure time is preferable and possibly the most effective one” (Graf &
Wessely, 2010).
Exercise as prevention
“The equivalent of 5 hours/ week of brisk walking was sufficient to achieve a reduced
risk of breast cancer, an amount consistent with the U.S. government’s guidelines for adults to
achieve additional health benefits beyond minimal activity” (Eliassen et al., 2010). This was a
general consensus among all the studies. It has been agreed upon by experts that any type of
exercise, especially brisk walking, is tremendously beneficial as cancer prevention. Furthermore,
“Physical activity has been shown to decrease circulating estrogen levels in postmenopausal
women, and lower circulating estrogen levels are associated with lower breast cancer risk”
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(Eliassen et al., 2010). This was an interesting finding as many cancers are hormone-driven and
female bodies could be labeled as hormone factory. It helped confirmed the link between
exercise and hormone levels in females and therefore directed future treatments and medical
interventions in the correct and more progressive direction. “The stronger association of physical
activity with risk of postmenopausal compared with premenopausal breast cancer hints at a
biological mechanism” (Ogunleye & Holmes, 2009). Strong correlation was established and
validated by recent studies performed. Nevertheless, past research was mostly done on
postmenopausal women so additional research is required for premenopausal group because
findings could be quite significant.
There is no doubt that engaging in proper lifestyle will help a person to prevent or delay
onset of many diseases, (such as diabetes or cardiac disease). Increasingly, there is a trend which
pinpoints proper lifestyle as the number one factor to prevent and combat cancer. There are some
uncontrollable factors to getting cancer (e.g. genetic predisposition), however according to
researchers Khan, Afaq, & Mukhtar (2010) “we can modify our lifestyle to reduce enhanced
threat of cancer and these modifications include a healthy diet, weight management, regular
exercise, reduction in alcohol consumption and smoking cessation.”
Exercise as adjunctive therapy
Any type of exercise as an adjunctive therapy is very important while undergoing cancer
treatment. It has been suggested, to all cancer patients, to engage in physical activity which
would be tolerable to them. This would help to decrease side-effects such as lymphedema,
depression, neuropathy, bone loss, and decrease in functional capacity. “These side-effects
ultimately led to impairments in health-related quality of life” (Eyigor et al., 2010). In many
cases, “systematic review and meta-analysis have shown that exercise (aerobic, resistance, Tai
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Chi Chuan) have a positive effect on quality of life, cardio-respiratory fitness and fatigue”
(Eyigor et al., 2010).
The new, break-thru study was performed on pilates exercise and its effect on breast
cancer. It is important to mention this study, as many of them (in the past) did not concentrate on
the particular type of physical activity. There has been sixty patients (age 18-75) participating in
the study and were selected through strict criteria. The study concluded that even pilates
increased flexibility of cancer patients (more so than any other type of exercise) “significant
differences were not observed and the results of this study needs to be supported by future
studies” (Eyigor et al., 2010).
Another study concentrated on the weight gain and survivorship connection to the breast
cancer. According to Djuric, Ellsworth, Weldon, Ren, & Resnicow (2010) “Weight gain is an
important concern that impacts on breast cancer outcomes and general health in survivorship.”
This specific study was exploring “whether or not women could comply with a weight control
program that is initiated at the beginning of chemotherapy for breast cancer” (Djuric et al.,
2010). The researchers used low-fat diet with abundance of fruit and vegetables and moderate
physical activity as means to achieve their results. It could have been described as life-style
modification study or life-style approach study. Its results were very positive as many patients
were able to maintain their desired weight when monitored. However, the drop- out rate was 25
percent, which somewhat skewed the results.
Exercise post-treatment
“Improved functional status is a primary goal in the rehabilitation of cancer survivors”
(Knols et al., 2010). One of the worst complications of the breast cancer is lymphedema.
“Vigorous upper-extremity activity and/or exercise have traditionally been proscribed for breast
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cancer patients and survivors because of the risk of developing lymphedema” (McNeely et al.,
2009). Not just this particular study (by McNeely et al.), but other studies in this literature
review agreed that it is important to keep the lymph circulating and let muscles act as a big pump
in order to achieve positive outcomes. This should also allow for improved cardiac function and
increased joint mobility.
Compared to other studies on lymphedema, this study did not used water-displacement
volumetry to measure limb circumference. This used to be the gold standard. Other equipment
called Perometer “has been shown to be highly reliable, and has been validated by comparison
with circumferential and water-volume measurements” (McNeely et al., 2009). Because of that
this study was quite innovative. The study added to the past research that “response to acute
upper-extremity exercise in terms of upper-limb volume and symptoms is similar between
affected and unaffected limbs in women with breast cancer who perform regular upper-extremity
exercise” (McNeely et al., 2009).
Conclusion
The literature review of this topic presented by various researchers showed the evidence
of the impact of exercise on the prevention of the breast cancer. Most of the evidence focused on
decreasing the risk of the breast cancer, the benefits of physical activity and healthy life-style.
Furthermore, it has been suggested that increased physical activity has a positive effect on cancer
patients and cancer survivors. It has been determined that it prolongs life, prevents recurrence of
the cancer and complications of the treatment (e.g. lymphedema). It can be said that exercise and
its effect was common denominator of all the studies.
The studies which were conducted in the past examined and analyzed this topic mostly as
a whole, but detailed study on particular types of the exercises are yet to be performed. There is
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not enough information pertaining to this issue. “Although greater activity has been related to
lower breast cancer risk, important details remain unclear, including type, intensity, and timing
of activity, and whether the association varies by subgroup” (Eliassen et al., 2010).
Further research on different type of exercise and its impact is warranted. Hopefully, this
could bring some very valuable results and knowledge regarding new interventions and their
application into the lifestyle of the patients, their treatments and therapy. “The diversity in the
activities prescribed (e.g., walking, strength and endurance, interventions with or without
counseling) reflects the absence of consensus on the optimal activity program for cancer
survivors” (Knols et al., 2010).
Additionally, it is author’s opinion, that it is important to re-evaluate different subgroups
when researching how exercise impacts them. From the presented articles, it is clear, that only
limited amount of the research was performed on premenopausal women, therefore results are
inconclusive. “The majority of studies have focused on postmenopausal breast cancer, although
there is also some evidence for a protective effect of physical activity on premenopausal disease”
(Parkin, 2010). Also, it would be interested to see how the results compare in Caucasian,
African-American, Asian and other populations.
To conclude this literature review, it is obvious that exercise and healthy lifestyle are the
most powerful warriors when it comes to cancer. This was demonstrated by all the research and
studies presented. Furthermore, they all loosely followed “American Cancer Society
recommendations for the prevention of tumor diseases” as mentioned by Eliassen, Hankinson,
Rosner, Holmes, & Willett (2010).
Recommendations are as followed:

30-60 min exercise on at least 5 days per week

Energy balance control
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Well-balanced nutrition

5 servings of fruits and vegetables per day

Moderate alcohol consumption (not more than 1 alcoholic drink for women and 2
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drinks for men per day)
It can be said that patients are most definitely in charge of their health and can
positively influence their status and medical outcomes. Even with cancer diagnosis, exercise and
modified lifestyle enables them to change their destiny!
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References
Djuric, Z., Ellsworth, J.S., Weldon, A. L., Ren, J., Richardson, C. R., Resnicow, K., et al. (2011).
A diet and exercise intervention during chemotherapy for breast cancer. Open Obes J, 3,
87-97. doi: 10.2174/1876823701103010087
Eliassen, A. H., Hankinson, S. E., Rosner, B., Holmes, M. D., & Willett, W. C. (2010). Physical
activity and risk of breast cancer among postmenopausal women. Arch Intern Med,
170(19), 1758-1764. doi: 10.1001/archintenrnmed.2010.363
Eyigor, S., Karapolat, H., Yesil, H., Uslu, R., & Durmaz, B. (2010). Effects of pilates exercizes
on functional capacity, flexibility, fatigue, depression and quality of life in female breast
cancer patients: a randomized controlled study (Vol. 46).
Graf, C., & Wessely, N. (2010). Physical activity in the prevention and therapy of breast cancer.
Breast Care (Basel), 5 (6), 389-394. doi: 10.1159/000322650
Khan, N., Afaq, F., & Mukhtar, H. (2010). Lifestyle as risk factor for cancer: evidence from
human studies. Cancer Lett, 293(2), 133-143. doi: 10.1016/j.canlet.2009.12.013
Knols, R. H., de Bruin, E. D., Shirato, K., Uebelhart, D., & Aaronson, N. K. (2010). Physical
activity interventions to improve daily walking activity in cancer survivors. BMC Cancer,
10, 406. doi: 10.1186/1471-2407-10-406.
McNeely, M. L., Campbell, K. L., Courneya, K. S., & Mackey, J. R. (2009). Effect of acute
exercise on upper-limb volume in breast cancer survivors: a pilot study. Physiother Can,
61(4), 244–251. doi: 10.3138/physio.61.4.244.
Ogunleye, A. A., & Holmes, M. D. (2009). Physical activity and breast cancer survival. Breast
Cancer Res, 11(5), 106. doi: 10.1186/bcr2351.
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Parkin, D. M. (2011). 9. Cancers attributable to inadequate physical exercise in the UK in 2010.
Br J Cancer, 105 Suppl 2, S38-41. doi: 10.1038/bjc.2011.482
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