Exercise and Cancer Survivorship

A cancer diagnosis often starts with symptoms of fatigue, and cancer treatments can make those symptoms worse. In this context, exercise may be misunderstood by those patients and clinicians who intuitively think that fatigue requires rest rather than physical activity. Exercise is not only a recommended treatment for fatigue but emerging evidence is finding it may also do additional things that improve cancer survivorship.

Fatigue

Scientific evidence points to exercise as a way to actually decrease fatigue, which is counter-intuitive for many… “How can exercise make me feel less tired, won’t it make me more tired?” The National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology (NCCN Guidelines) recommend exercise for reducing fatigue related to cancer and cancer treatment. Some excerpts and links to the guidelines are below:

National Comprehensive Cancer Network

• The National Comprehensive Cancer Network^® (NCCN^®) is an alliance of 26 of the world’s leading cancer centers, working together to develop treatment guidelines for most cancers, and dedicated to research that improves the quality, effectiveness, and efficiency of cancer care. http://www.nccn.org/

Exercising During Cancer Treatment

http://www.nccn.org/patients/resources/life_with_cancer/exercise.aspx

Exercise Reduces Fatigue

Research has found no harmful effects on patients with cancer from moderate exercise and, in fact, has demonstrated that those who exercised regularly had 40% to 50% less fatigue, the primary complaint during treatment.

Fighting Cancer Fatigue

http://www.nccn.org/patients/resources/life_with_cancer/fatigue.aspx

Exercise

It may require considerable effort to get up and move around, but increasing your physical activity may actually reduce fatigue. Studies show that cancer patients who exercise are less tired and depressed and sleep better than patients who don’t exercise.

Category 1: Based upon high-level evidence, there is uniform NCCN consensus that the intervention is appropriate. Exercise is category 1.

A practical example of how inactivity and activity affect muscles is this: if you’ve ever broken an arm or leg and had it put into a cast, you may remember how withered the muscles were when the cast was removed. This is because the muscles were not used as much while in the cast. ‘Use it or lose it’, this applies to muscles, and also can apply to cancer patients who might rest, nap, or sit excessively – if the muscles are not used they will wither (decrease in size, strength, and endurance). This can start a downward negative spiral of fatigue – tired from treatment, rest more, more rest, weaker smaller muscles, weaker smaller muscles make daily activities more tiring, more fatigue, more rest, the more rest, the weaker the muscles, etc. Many cancer patients also gain weight after treatment, which can fatigue weak muscles even more.

Immunity

Exercise can boost our immune system, and since cancer cells have the ability to evade detection from our immune system, exercise might be worthwhile for more than just reducing fatigue or body fat, perhaps acting more like immunotherapy.  Moderate intensity or volume of exercise, including one of the few exercise studies on CLL¹, has been shown to positively affect proportions of T-cells and the mobilization of Natural Killer cells, both of which can kill abnormal, virally infected, and cancer cells^1,2,3,4.  However, some research found that high volumes and intensity of exercise had a negative effect on immune cells, suggesting that a lot more exercise might not be better^5,6.

“I don’t like exercise”

Finally, some cancer survivors may be confused about what counts as exercise, they may not liking going to a gym, formal exercise classes, or activities like running. Fair enough, we are all different, and thankfully so are the options for ‘exercise’. For people who are more fit or younger, moderate amounts and intensity of running may be ideal, which provides a lot of benefit in a short amount of time. For others, walking their dog or gardening may be a perfect ‘exercise’. For those who are less fit, in treatment, or just starting out, puttering around the house/hospital, resting, puttering some more, resting, and repeating this throughout the day may be the best way to start moving more and to avoid too much physical inactivity.

Importantly, viewing exercise as a complimentary treatment strategy may increase the motivation to ‘stick with it’, helping exercise to become a part of lifestyle changes that often occur after diagnosis. Exercise increased treatment completion rates among breast cancer patients⁷, which may improve treatment outcomes. Additionally, some cancers, CLL included, can be cured with stem cell transplantation, but not all patients are eligible, and physical fitness is a consideration.

By choosing activities appropriate for you and that you like, exercise can become an important part of a cancer treatment strategy, helping to: combat fatigue, improve immune function, manage weight, complete treatments, reduce treatment side effects⁸, decrease mortality risk and hospitalization days associated with stem cell transplantation⁹, and improve quality of life¹⁰.

Further reading and references

Here are a few links to some blog posts I’ve written about ‘exercise’ and surviving cancer/treatments that you may find useful:

• What is exercise for cancer patients? It’s all relative.
• Sweat the little things.
• Exercise and immunity.

References:

1. Perry C., et al. Reciprocal changes in regulatory T cells and Th17 helper cells induced by exercise in patients with chronic lymphocytic leukemia. Leuk Lymphoma. 2012; Sep;53(9):1807-10
2. Spielmann, G., et al. Aerobic fitness is associated with lower proportions of senescent blood T-cells in man. Brain, Behav Immun 25 (2011) 1521–1529.
3. Bigley AB et al. Acute exercise preferentially redeploys NK-cells with a highly-differentiated phenotype and augments cytotoxicity against lymphoma and multiple myeloma target cells. Part II: Impact of latent cytomegalovirus infection and catecholamine sensitivity. (Article in Press) Brain, Behav Immun (2015).
4. Bigley AB et al. Acute exercise preferentially redeploys NK-cells with a highly-differentiated phenotype and augments cytotoxicity against lymphoma and multiple myeloma target cells. Brain, Behav Immun. Jul; 39: 160–171.
5. Coagrove C et al. The impact of 6-month training preparation for an Ironman triathlon on the proportions of naïve, memory and senescent T cells in resting blood. Eur J Appl Physiol (2012) 112:2989–2998.
6. Nieman DC. Upper respiratory tract infections and exercise. 1995 Dec; 50(12): 1229–1231.
7. Courneya KS et al. Effects of aerobic and resistance exercise in breast cancer patients receiving adjuvant chemotherapy: a multicenter randomized controlled trial. J Clin Oncol. October 1;25(28):4396-4404.
8. Streckmann F et al. Exercise program improves therapy-related side-effects and quality of life in lymphoma patients undergoing therapy. Ann Oncol. (2014) 25 (2): 493-499.
9. Wood WA et al. Cardiopulmonary fitness in patients undergoing hematopoietic SCT: a pilot study. Bone Marrow Transplantation (2013) 48, 1342–1349.
10. Mishra SI et al. Exercise interventions on health-related quality of life for cancer survivors. Cochrane Database Syst Rev. 2012 Aug 15;8:CD007566.

Ken Martin is a survivor of: Hodgkin’s, Follicular, and Diffuse Large B Cell lymphomas, plus an allogeneic stem cell transplantation.  He advocates for more and better exercise-oncology research.  Ken was the 1984 & 1985 US marathon champion, has broken 4 minutes for the mile, studied biology and exercise physiology, and is a member of the American College of Sports Medicine.  

Originally published in The CLL Tribune Q3 2015.