Exercise For Cancer Prevention and Treatment

By Marianne Morano, M.S., ACSM, CWC

Introduction

As February is Cancer Prevention Month this article will focus on growing awareness for cancer prevention, and treatment in the event of an unfortunate diagnosis, via exercise.  In 2016, approximately 1,685,210 new cases of cancer were diagnosed in the United States, and approximately 595,690 people died from the disease.  It is estimated that the number of new cancer cases will rise to 22 million within the next two decades.

What if you could greatly reduce your risk of developing cancer, improve your chances of successful recuperation, and diminish your risk of cancer recurrence if the worst - case scenario happened?

Research

Extensive research with compelling evidence suggests that exercise is key in cancer prevention and cancer care.  Studies from the Journal of Medicine and Science in Sports and Exercise conclude that physically active men and women have a 30-40% reduction in the risk of developing colon cancer, and women have a 20-30% lower risk of developing breast cancer with as little as 30 – 60 minutes of moderate to vigorous exercise, compared with inactive men and women.  The most recent evidence published in the Journal of the American Medical Association (JAMA) concluded that exercise is associated with a lower risk of 13 cancer types.  Exercise alters T cells to a more effective disease-fighting form, boosting the immune system to fight emerging and existing cancer cells. This explains the benefit of exercise for cancer prevention and treatment. In fact doctors worldwide have concluded that if exercise could be bottled in a pill, it would be the singly most widely prescribed drug due to its numerous health benefits.

A recent study found a 50% reduction in developing cancer in mice that were active, due to adrenaline release from exercise that circulates natural killer cells to kill off and eliminate cancer cells. The studies to support exercise as potent cancer prevention are endless.  In the Journal of the National Cancer Institute, it was stated that due to tissue oxygenation that occurs with aerobic activity, those with cancer had improved effectiveness of chemotherapy.

As demonstrated by these few research studies, exercise is beneficial in cancer prevention and treatment, so how much and what type of exercise is recommended?

Exercise Guidelines For Cancer Prevention

The American College of Sports Medicine and the American Cancer Society recommend a minimum of at least 30 minutes of moderate activity 5 days per week (150 minutes) or 75 minutes of vigorous activity per week.  As 150 minutes of moderate activity per week is recommended for health and a great start for beginners, studies show that 300 minutes per week of moderate activity, or 150 minutes per week of vigorous activity for those already exercising regularly adds additional protection from cancer and weight gain.  In most recent studies, those with 7 hours a week of brisk walking, or 2.5 hours a week of jogging experienced the lowest incidence of cancer risk.  Both aerobic and resistance training are recommended to prevent and treat cancer.   Resistance training is recommended 2-3 days per week with 8-10 exercises of 10-12 repetitions for at least one set per session.

With regard to prevention some exercise is better than none even if you do not achieve the recommended amount of exercise daily.  Perform some activity above typical daily activities, and limit sedentary behavior such as sitting, watching TV or other screen based activities.  Note that even if you exercise but spend a lot of time sitting after the exercise session, you are still at greater risk for developing cancer, and all disease, as ‘sitting is now considered the new smoking.’

Suggestions to Reduce Sedentary Behavior

Things To Consider

• Achieve and maintain a healthy weight for life.
• Engaging in regular physical activity and reduction in high caloric food is key in maintaining weight
• If you are over 40 or have disease, seek physician approval before beginning an exercise program, specifically vigorous exercise
• Always begin each exercise session with a 5-10 minute warm up
• End each exercise session with a 5-10 minute cool down followed by stretching all major muscle groups
• Maintain weight by balancing energy in from calories, and energy out from exercise
• Track food and exercise to achieve energy balance to prevent cancer
• Types of activity include but are not limited to:
  • Light Intensity
    • Casual walking
    • Activities of daily living
    • Gardening
    • House work
    • Shopping

• Moderate Intensity
  • Climbing stairs
  • Brisk walking
• Vigorous Intensity
  • Scheduled activity such as: jogging, cycling, hiking, resistance and bodyweight training, yoga, or any type of exercise session.  See table for exercise suggestions

*Adapted from American Cancer Society Position Stand on Nutrition and Physical Activity for Cancer prevention

The health benefits of physical activity and exercise with regard to cancer prevention are cumulative over time.  The longer you exercise regularly, the greater the protection; however, adoption of regular exercise at any stage of life reduces the risk of cancer.

Exercise Prescription For Cancer Prevention

According to Wikipedia Exercise Prescription (ExRx) commonly refers to the specific plan of fitness-related activities that are designed for a specified purpose, customized for an individual, often developed by a fitness or rehabilitation specialist for the client or patient. 

There is a science to writing an ExRx and as it is individualized according to needs and abilities, for the purposes of this article the ExRx will be general in nature incorporating basic principles of Exercise Science. 

The basic principles include planning for F.I.T.T., Fit, Intensity, Time and Type of exercise.  In addition, specificity, overload, reversibility and progression must be considered.   Before determining the type and how much exercise you should incorporate into your plan, it is imperative to perform basic fitness assessment tests for cardiovascular endurance, musculoskeletal strength and endurance, and flexibility.  Examples of these assessments include but are not limited to:

• Queen’s College or YMCA step test for cardiovascular endurance
• 1 RM or Push up tests for muscular strength
• Partial curl up test for muscular endurance
• Sit-n-reach test for flexibility

Before performing any fitness assessment tests, it is recommended to enlist a fitness professional to assist in assessing, analyzing and prescribing exercise.

An example of F.I.T.T. is:

• Frequency: 5 days per week
• Intensity: moderate
  • Intensity is the most difficult to determine.  There are formula’s and tests to determine the best intensity for each individual and is best determined by a fitness professional with experience in Exercise Prescription.  Always begin with a lighter intensity and gradually increase as tolerated by the body
• Time: 30 minutes per session
• Type: Brisk walking
• Specificity: cardiovascular training as walking is an aerobic activity
• Overload: it must feel like work to increase cardiovascular fitness so walking at a pace that elevates heart rate and breathing rate to a point of feeling the effort without overexertion
• Progression: intensity and duration must gradually increase to accommodate adaptation that occurs with exercise.  Continually and gradually increase the intensity by walking faster or adding hills and gradually add more time to the session
• Reversibility: ‘use it or lose it’ applies as it takes 2-3 weeks of not exercising to reverse all that is gained

A basic, beginner ExRx including aerobic training, resistance training & flexibility is as follows:

To allow for progression, the above ExRx is recommended for 2 weeks.  At the end of 2 weeks the fitness professional will assess progression and adjust the ExRx accordingly.  As the client progresses, the intensity and duration will be increased.  As stated, this is a general ExRx to demonstrate how to schedule exercise for health and disease prevention. 

Exercise Guidelines For Cancer Treatment

Hopefully, positive lifestyle changes will prevent cancer; however, if cancer has already been diagnosed, consider these guidelines for exercise and cancer treatment.

Studies show that exercise may reduce the risk of developing a second cancer, or the reoccurrence of a primary cancer.  The greatest benefit of exercise for cancer patients is the increase in survival rate of 50 – 60%. Mechanisms by which exercise improves cancer survival are numerous and some examples include: increased immune function & the reduced risk of other chronic diseases, reduced body fat, decreased depression and overall increase in general health and well being. 

Benefits of Exercise in Cancer Patients*adapted from Vario Health Institute; Newton & Galvao, PhD

Keep in mind that tolerance varies depending on the individual.  An exercise program must be safe and individualized for cancer treatment.  It should be based on activities the patient enjoys plus any physical limitations.  In addition, the type and stage of cancer, the treatment plan, and the stamina and fitness level of the patient must be considered before designing an exercise prescription.  Begin slowly, and gradually increase exercise as tolerated.

Always seek physician approval, and enlist a Clinical Exercise Physiologist, or Personal Trainer with cancer certification before beginning an exercise program.  Have the cancer care ‘team’ oversee exercise goals and programs and adjust the plan as needed.  The cancer team will also:

• Check white and red blood counts to see if it is safe to exercise
• Check mineral levels to ensure safe sodium and potassium levels
• Check symptoms to see if ankles are swollen, if there is abnormal bleeding, skin irritation and many other symptoms that suggest exercise avoidance
• Assessments to ensure safety with resistance and aerobic training

After treatment ends, many of the side effects subside and intensity and duration of exercise may be increased slowly.  “The American Cancer Society recommends that cancer survivors take these actions:”

• Take part in regular physical activity.
• Avoid inactivity and return to normal daily activities as soon as possible after diagnosis.
• Aim to exercise at least 150 minutes per week.
• Include strength - training exercises at least 2 days per week.

Things To Consider

• Begin slowly and see what is tolerated before progressing.  A few minutes a day is recommended
• Always begin with a warm up and end with a cool down and stretching.
• Short periods of exercise with frequent rest periods
• Include exercise that increases muscle mass and bone strength using resistance bands or light weights
• Include aerobic exercise and flexibility
• Add exercises that focus on large muscle groups such as: chest, thighs, abdominals, and back
• If fatigued easily, try splitting a 30-minute session into 3 ten-minute sessions throughout the day.
• Listen to your body and do not push yourself while in treatment, and rest as needed

Keep Exercise Simple and Fun

• Reducing stress is a huge part of cancer prevention and treatment.  Practice relaxation exercises in addition to physical exercise
• Set long and short term goals
• Do something new to keep things fresh.  Try yoga, dancing or tai chi, for example
• Work with a buddy for motivation, fun and accountability
• Track progress and reward achievements

Remember that during treatment, fatigue is a huge issue.  In the past, rest was recommended, and today aerobic exercise instead of rest is recommended to greatly reduce fatigue.  Schedule exercise sessions when you are feeling your best.  This may be at different times on various days, so flexibility is required when planning exercise sessions.

Exercise Prescription (ExRx) For Cancer Treatment

Following the above guidelines, the Oncologist and Clinical Exercise Physiologist work together to design a customized ExRx for the patient receiving or recovering from cancer treatment.  As each individual’s disease is different, the ExRx must be designed accordingly to take all considerations into account to deliver the most effective ExRx.

As such, it is impossible to provide an ExRx that is individualized and for the purposes of this article, a general ExRx is outline below.  As with the ExRx for cancer prevention, F.I.T.T (frequency, intensity, time and type) along with specificity, overload, progression and reversibility must be included.

It is recommended that cancer patients perform aerobic activity (walking, cycling, for example) either continuously for 20 – 60 minutes or intermittently throughout the day if longer sessions are not well tolerated for 3-5 days per week at a light to vigorous intensity depending on the patient. 

• For example, Joe might be in remission and tolerates 60 minutes of exercise at one time, whereas, Tom might still be in treatment with side effects that only allow 20 minutes of exercise at a time, so he may have 3 sessions of 20 minutes each throughout the day.
• In addition to aerobic activity, resistance training is recommended as tolerated to help build muscle and bone 1-3 days per week, at a low to high % of 1RM as per ability, with 6-12 repetitions of 8-10 exercises of major muscle groups for a total of 1-4 sets.
• Flexibility training and balance training are recommended for all major muscle groups at 2-4 sets for 2-3 days per week.

A basic, beginner ExRx including aerobic training, resistance training & flexibility is as follows:

To allow for progression, the above ExRx is recommended for 2 weeks.  At the end of 2 weeks the fitness professional will assess progression and adjust the ExRx accordingly.  As the client progresses, the intensity and duration will be increased.  As stated, this is a general ExRx to demonstrate how to schedule exercise for health and disease prevention. 

As stated, it is extremely difficult to determine the intensity level for aerobic or resistance training for a person not skilled at exercise prescription, and it is imperative to seek advice from a trained fitness professional before beginning or creating an exercise program.

CONCLUSION

Exercise is proven to be a critical factor in prevention and management of cancer. Being physically active throughout life reduces risk of many cancers. After diagnosis of cancer, a proper exercise regimen improves symptoms prepares the patient for a more favorable surgical outcome, ameliorates treatment side effects, enhances psychological well-being, and increases survival and reduction in risk of a second cancer or reoccurrence of the primary cancer.

As such, regular exercise is highly recommended and must be encouraged in all populations, particularly those at higher risk of cancer. Further, exercise as medicine must be incorporated in the routine clinical care of cancer patients to improve quality of life, as well as reduce morbidity and mortality. 

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Marianne E. Morano, M.S., ACSM, CWC serves on Cancer Schmancer's Medical Advisory Board. She is a Clinical Exercise Physiologist and the CEO and Founder of Fit or WHAT, Inc. Her mission is to empower clients and the community to achieve their personal best through healthy lifestyle programs, creating longevity and quality of life.