The cancer journey can begin many ways. For some, it begins with an abnormal screening test. For others, it begins with a symptom. Yet, for others, the journey begins with the diagnosis of a family member, followed by genetic testing. It was estimated that 1,658,370 Americans would be diagnosed with cancer in 2015 (2). Of these, it was estimated that 66.5 percent would live five or more years after their cancer diagnosis. For diagnoses of breast and prostate cancers, approximately 89 and 99 percent, respectively, of all incident cases are expected to live at least five years beyond their diagnosis. Five-year survival after endometrial, colon, and lung cancers is 82, 65, and 17 percent, respectively. These widely differing survival rates are a reflection of two realities. First, “cancer” should really be “cancers,” plural. There are over 200 types of cancer. Further, progress in early detection and treatment success has varied greatly across these many different types of cancer. As a result, the population of 14.5 million cancer survivors alive in the United States today is tremendously diverse (7).
Causes of Cancer
Cancer occurs when a small number of cells in a particular body system begins to replicate more quickly than expected and without normal and expected planned cell death. All cells in the body replicate themselves, and all cells in the body should undergo planned cell death. When genetic changes occur, cells may begin to grow out of control. If the cells are replicating quickly and have no ability to spread to another part of the body, the growth (also called a tumor) is considered benign. If the cells have the characteristics that would allow them to grow beyond the tissue where they start, spreading through the blood or lymphatic vessels, the tumor is considered malignant. There are many reasons cells start to grow more quickly and fail to die as expected. People may have a gene mutation that was present at birth, passed on by a parent. An example is the BRCA1 and BRCA2 gene mutations. Both substantially increase the lifetime risk for breast and ovarian cancer among those who test positive for these mutations.Another reason for genetic changes that might contribute to the development of cancer is environmental. An example is exposure to asbestos and the development of mesothelioma.
Finally, there are lifestyle factors that explain the development of cancers as well. Cigarette smoking is the number one preventable cause of cancer. If you smoke and your goal with lifestyle change is to reduce your risk of cancer, quitting smoking should be your highest priority. In addition, it is estimated that one-third of all cancers in the United States are preventable with exercise, healthy eating, and weight control (9). Therefore, the exercise and nutrition information in this book is relevant for cancer prevention. It is also important to recognize that the reason any given person develops cancer is complex. People should not feel that they “caused” their cancer through their actions or inactions. This chapter focuses on how to recover the best possible function you can after a diagnosis of cancer.
Healthy Approaches to Managing Cancer
A diagnosis of cancer has been called a “teachable moment” with regard to developing and maintaining a healthy lifestyle. Published peer-reviewed evidence supports the benefits of healthful nutrition, weight control, and regular exercise for those who have had a diagnosis of cancer (10, 12, 16). This section outlines the benefits and provides guidelines on these lifestyle interventions. In addition, it provides guidance regarding preexercise precautions and evaluations, exercise prescription advice, and program suggestions for people currently undergoing treatment and those who have completed treatment. Two categories of concerns for cancer survivors are (1) persistent adverse treatment effects and (2) recurrence and survival; both of these are discussed.
Focusing on Nutrition
Every few years, the American Cancer Society (ACS) gathers a group of experts to discuss guidelines for nutrition (and physical activity) for people who have been diagnosed with cancer. The most recent publication from this process is from 2012 (12). The experts divide the nutrition guidance into sections: active treatment and recovery, living free of cancer or with stable disease, and living with advanced cancer. The most recent version of these guidelines from ACS is summarized in table 14.1 (12) and discussed in the following section.
If you are currently undergoing active treatment, your dietary focus should be on making sure you meet your nutrient and calorie needs, maintain a healthy body weight, avoid losing muscle mass, manage side effects related to nutrition, and improve quality of life. If you are struggling with any of these issues, ask for help. You can request that your doctor make a referral to a Registered Dietitian or another type of nutrition professional to help you as part of your cancer care team.
Many patients consider using nutritional supplements during cancer treatment. There are two things to know about nutritional supplements and cancer treatment outcomes. First, your doctor needs to know what you are using, given that some supplements may decrease the effectiveness of conventional treatments. Second, there is no evidence that nutritional supplements improve cancer treatment outcomes. In general, focus on getting your nutrients from food-based sources rather than supplements. During recovery from treatment, there may still be symptoms and side effects of treatment that could be helped by specific nutritional interventions. Achieving and maintaining a healthy body weight remains important, whether this means losing or gaining weight. Nutrition counseling can assist with both of these issues.
When you are at the point of living disease-free or with stable disease, the ACS recommendations for achieving and maintaining a healthy body weight remain in place. There is increasing evidence that being overweight or obese is associated with a worse prognosis for people who have had a diagnosis of cancer. The nutrition guidance for cancer survivors is to eat a variety of healthy foods from plant sources, limit the amount of processed meat and red meat, consume 2.5 cups or more of vegetables and fruits each day, and choose whole grains rather than refined grain products.
For persons living with advanced cancer, the focus of nutrition guidance is on controlling symptoms and ensuring adequate calorie and nutrient intake. Medicines that can increase appetite might be used. The use of nutritional supplements and intravenous feeding can also be helpful in some patients with advanced cancer. The ACS website (www.cancer.org) has much more detailed information about the role of nutrition across the cancer journey, from diagnosis to prevention of cancer recurrence and for those living with advanced cancer (1).
Role of Exercise During the Cancer Journey
During the time period just before and after cancer diagnosis, exercise may be most useful for reducing the anxiety associated with waiting for test results. The journey continues with the active treatment period. For many people, the first type of cancer treatment is surgery, which sometimes occurs within weeks of diagnosis. Exercise can often continue right up until the day of surgery. The specific benefits of presurgical exercise are just beginning to be explored. The hypothesis is that exercise for even a few weeks before surgery may improve immediate surgical outcomes and decrease recovery time, including less time in the hospital.
During the time period immediately following surgery, the body needs to spend all of its energy healing. The rule of thumb for returning to exercise is anywhere from four to eight weeks after surgery, depending on your condition and the extent of the surgery. If adjuvant treatments such as radiation and chemotherapy are recommended, exercise can and should continue during this period. Exercise tolerance varies throughout the cycles of treatment. For example, if chemotherapy is received every three weeks, there may be a few days immediately after the infusion when exercise needs to be curtailed or even stopped. However, the recommendation from multiple leading organizations is that cancer patients continue to exercise throughout their treatment (10, 12, 16). At the end of chemotherapy or radiation treatment, some oral therapies may still be used. From this point and to the end of life, exercise is recommended and may be undertaken in a manner specifically designed to minimize adverse effects of treatment and maximize survival.
Focusing on Physical Activity
The benefits of exercise for persons who have had a diagnosis of cancer have been broadly documented and include both physical and psychosocial benefits (4, 5, 17). Hundreds of randomized controlled trials have been completed that document benefits of specific exercise regimens for specific outcomes (17). Exercise is like medicine in that it must be prescribed and dosed specifically for the outcome of interest. For example, low-intensity aerobic activity has been shown to improve fatigue and quality of life. However, to improve function and bone health may require strength training. To improve balance may require yet another type of activity (e.g., yoga). There is research to support the benefit of exercise on reducing risk for recurrence of breast and colon cancer as well (6).
ACSM, ACS, and National Comprehensive Cancer Network provide guidance for exercise after a diagnosis of cancer (10, 12, 17):
· Avoid inactivity, and return to activity as soon as possible after surgery.
· Build to 150 minutes per week of aerobic activity (e.g., walking, biking, swimming, dancing).
· Perform progressive strength training two to three times per week.
· Do flexibility activities on most days of the week.
The overall recommendations after therapeutic interventions (e.g., surgery) are to avoid inactivity and return to regular activity as soon as possible, including aerobic activities, resistance training, and flexibility exercises. With regard to aerobic exercise, low intensity is typically recommended. The ACSM guidelines are the only ones that specify an intensity of moderate to vigorous intensity, and this is based on the documentation of benefits from aerobic exercise at higher intensity levels.
Precautions for Exercise
As discussed earlier, many cancer survivors experience one or more persistent adverse effects of their cancer treatments. Some of these may alter the safety of certain types of exercise, which would suggest that survivors with these issues undergo a preexercise evaluation before getting started to avoid the potential that exercise might do more harm than good. In addition, most cancer survivors are older adults who enter their cancer journey with one or more chronic disease diagnoses, which also may alter the safety profile of exercise. This section discusses whether survivors should seek a preexercise evaluation by a well-trained exercise professional or physical therapist before starting exercise and then whether supervised or home-based activities are recommended.
Q&A
Where can I find a fitness professional to help guide me in my exercise program?
The ACSM, along with the ACS, has developed a certification that recognizes fitness professionals with expertise in working with cancer patients. Certified Cancer Exercise Trainers (CETs) can design and administer fitness assessments and exercise programs based on an individual’s cancer diagnosis, treatment, and status. To find a CET near you, see the ACSM’s Profinder webpage: http://certification.acsm.org/pro-finder.
How do you know whether you can proceed with exercise in a community or home-based, unsupervised setting versus needing a more structured, supervised exercise program after cancer? First, if you would like a supervised, structured program, go find that supervised program! Second, if you are going to do low-intensity activity such as walking, you can likely proceed without supervision or evaluation. However, if you intend to progress beyond low intensity, to include strength training or to do sports and higher-intensity outdoor activities (e.g., hiking mountains, skiing), it would be useful to understand your risk level. The ACSM and the National Comprehensive Cancer Network both have published guidelines on this topic (see table 14.2 for a summary) (10, 16). There are three categories in both sets of guidelines: low-risk individuals who can exercise unsupervised without prior evaluation, moderate-risk individuals who are advised to undertake an evaluation to determine whether they need supervision, and high-risk individuals who are advised to find a supervised exercise program for their own safety.
The majority of individuals diagnosed with cancer are over age 65 and have at least one other chronic disease diagnosis at the time of cancer diagnosis (e.g., hypertension, obesity, asthma, arthritis). Therefore, the beginning exercise program draws heavily from the advice in chapters that focus on those specific conditions and the chapter on exercise for older adults. Ideally, starting an exercise program in a supervised setting helps to ensure that the exercises are being done properly before one continues the program in a community or home setting.
Physical Activity Recommendations
There are six elements common to all of the exercise components, toward the goal of ensuring that exercise is both safe and beneficial: frequency, intensity, time, type, volume, and progression (FITT-VP) (3, 19). Frequency refers to the number of times the activity occurs per week. Intensity refers to the degree of difficulty. This can be stated in absolute terms (e.g., lifting a given weight such as a 5-pound [2.3 kg] dumbbell) or in relative terms (50 percent of maximum effort). Time refers to the duration of a given exercise or session of exercise. Type refers to the mode of exercise, such as stationary bicycling, walking, or jogging. Volume is defined as the total amount of exercise done, which is a combination of intensity and time. Finally, progression refers to the need for exercise to progress with regard to volume in order for benefits to continue to accrue. One can increase the volume by increasing intensity or time.
Aerobic Exercise
To start an aerobic exercise program as a beginning exerciser, the frequency should be two to three times per week. Once you are comfortable with this frequency (e.g., no increase in fatigue or other adverse effects), another session can be added per week up to six sessions per week. There should always be at least one day of rest from aerobic exercise.
As to intensity, one easy way to determine this is to use the “talk but not sing” rule. If you can sing (hold a note) while doing your aerobic exercise, you are not working hard enough. By contrast, if you cannot talk while doing aerobic exercise, you are working too hard. Intensity needs to progress, however, for benefits to continue to accrue. Thus, it would be advisable to take note of your pace on a track or pathway or of your workload on any gym equipment you are using. For example, you could note how many blocks you can walk in your daily walking sessions and increase the number of blocks walked within a given time period as you continue. Tracking this information is helpful for ensuring that you get the most out of your workouts.
Regarding time per aerobic exercise session, a beginning exerciser who is starting after a cancer diagnosis might want to begin with as little as 5 to 10 minutes per session to be sure that the activity is tolerated. This is increased by 10 percent per week. For example, if you choose to do three 10-minute sessions in your first week of a walking program, the next week you would do 33 minutes, or 11 minutes per session. Within several months, you would be up to 30 minutes per session.
Typically with respect to the volume and progression of aerobic exercise for beginning exercisers after cancer, 30 minutes per week is a starting point, and then the time or intensity can be increased. The intensity can be increased by 10 percent per week, as can the time. However, it might be advisable to increase one of these per week, not both. That could mean increasing time one week and intensity another week.
Various types of aerobic exercise can be included in your exercise program. One common approach is a walking program. For those with balance or peripheral neuropathy, however, a stationary bicycle might be the best first step to aerobic fitness. The most important aspects of choosing a type of aerobic exercise are safety and enjoyment. If you get hurt or don’t enjoy the activity, you won’t keep doing it regularly.
Resistance Training
Resistance (strength) training is not just for young people and isn’t just about lifting heavy weights in order to create bigger muscles and look better on the beach. Strength training can help cancer survivors regain strength that is lost during active treatment and is also helpful for promoting bone health (13, 15, 18). Strength training can help older adults by ensuring that they continue to have the strength to get on and off the toilet, climb stairs, carry groceries, and do other common functional tasks. Older adults lose muscle mass as they age, and cancer treatment can exacerbate that process. Strength training may be more important than aerobic exercise for some survivors.
The recommended frequency of strength training is two to three times per week. The time it takes per session may vary, but 20 to 30 minutes is adequate. The type could include dumbbells, variable-resistance machines, or strength training activities performed in a class.
Even if you have done strength training in the past, it would be advisable to start with very low levels of resistance during and after your cancer treatment. There is often a period of inactivity during active cancer treatment. This can result in loss of muscle mass and strength. Adjuvant treatments (e.g., chemotherapy and radiation) may also result in loss of muscle mass and strength. Thus, to avoid injury, it is recommended that those living with and beyond cancer start with low resistance. If you are using dumbbells, this would translate to 1 to 5 pounds (0.45 to 2.3 kg) per exercise. If you are using variable-resistance exercise machines at a fitness facility, start with one or two plates on each machine.
The type of strength training you do is not as important as doing it regularly. If you prefer to exercise at home, you might want to get a set of dumbbells or adjustable-weight dumbbells. If you enjoy exercising with others, you might like using variable-resistance machines in a circuit or in a class led by an instructor.
Progression of resistance should be slow after a cancer diagnosis for several reasons. First, many survivors experience a period of inactivity between the time of diagnosis and the time when the surgeon indicates it is safe to begin normal daily activities again. Deconditioning occurs when exercise is stopped. The extent of the deconditioning is determined by the length of time spent not exercising. When one is starting or returning to exercise after a period of deconditioning, there is a higher likelihood of muscle injury from overdoing. There is also an inflammatory response that occurs when one progresses resistance too much (e.g., a 50 percent increase, such as going from 5 to 10 pounds [2.3 to 4.5 kg] from one session to the next). This is pertinent because cancer-related fatigue is thought to be related to inflammation. Further, an inflammation-related adverse effect of cancer treatment called lymphedema can cause swelling of the area of the body affected by cancer. Lymphedema results from an increase in protein-rich fluid, which can happen with increased inflammation and can occur in the arms, breasts, and torso of breast cancer survivors and in the lower body after bladder, testicular, and gynecologic cancers, as well as after melanoma.
Although cancer survivors can safely do resistance training, in order to avoid increasing inflammation or muscle injury after deconditioning, they are advised to start with low weights (below 5 pounds [2.3 kg] for dumbbells, one or two plates on variable-resistance machines) and progress resistance in the smallest possible increments. As always, allow changes in symptoms to be your guide. Finally, if you find that you need to take an “exercise holiday” (e.g., because of caring for an ill relative, vacation), be sure to back off on the resistance used in your strength training exercises. If you take three weeks off, start over with the lowest weight and rebuild. To avoid injury and any excessive inflammatory responses, maintain a regular strength training routine performed at least twice weekly. But make sure you have at least one day between each session to allow the muscles to recover.
The exercises you perform should work the major muscle groups: chest, back, shoulders, arms (biceps and triceps), front of thighs, back of thighs, buttocks, and calves. You should also do exercises for the muscles commonly referred to as the core: the abdominal muscles and lower back. The exercises shown in chapter 6 of this book would form an excellent program for cancer survivors. The only change would be to start at a low weight and to progress more slowly than indicated in chapter 6.
Q&A
Are there benefits of yoga for cancer survivors?
There is evidence that yoga can help cancer survivors sleep better (11). Further, many cancer survivors enjoy yoga for the benefits of relaxation and quality of life improvements. The challenge in recommending yoga to cancer survivors is that there are many types of yoga, and not all of them would be suitable for cancer survivors. Vinyasa, Bikram, Hot, Ashtanga, Power, Jivamukti, and Kundalini yoga might be more advisable for cancer survivors who had been practicing these types of yoga for a long time before diagnosis.
The forms of yoga that might be more advisable for cancer survivors include Yin, Hatha, Iyengar, and Restorative yoga. Ultimately, there is no hard and fast rule to determine what is safe for a specific person. Thus, use caution when approaching yoga in all forms by starting slowly, progressing slowly, and letting symptoms be your guide. This is good advice for all other forms of exercise as well. There is value to moving more. If you are attracted to a form of exercise that isn’t discussed in this chapter and wonder whether it would be advisable for you as a cancer survivor, there is a simple way to proceed: with caution. Do a small amount of the activity and see how it feels. Progress the time and intensity gradually. And, as always, allow your symptoms to be your guide.
Flexibility and Neuromotor Exercises
With age, range of motion generally decreases, which can make it difficult to perform common activities that require reaching or twisting. The deconditioning that commonly surrounds diagnosis and surgery for cancer patients can also increase stiffness. To maintain a healthy range of motion and optimal function of all muscle groups, it is useful to do flexibility exercises. In addition, although specific benefits related to cancer have not been studied, inclusion of neuromotor exercise involving balance, agility, coordination, and gait may be considered as part of a general exercise program, especially for older adults (3). The flexibility program outlined in chapter 7 would be an outstanding program for cancer survivors, and options for neuromotor exercises are provided in chapter 8. No adaptations are needed unless symptoms indicate otherwise.
Effects of Cancer Relevant to Exercise
Developing exercise programming for such a diverse population requires consideration of physical and medical conditions before cancer diagnosis. Other important considerations include where the cancer is in the body, the body systems affected by the cancer and its treatments, and where survivors are with regard to their cancer journey.
Prediagnosis Physical and Medical Condition
The effect of a cancer diagnosis on the ability to exercise, as well as the ways in which exercise benefits a cancer survivor, varies according to how well one is at the point of diagnosis. As an extreme example, consider an 18-year-old testicular cancer survivor who was quite physically fit at the point of diagnosis compared to an 80-year-old man with prostate cancer who was obese, diabetic, and hypertensive when diagnosed. Clearly, any exercise advice needs to account for prediagnosis fitness, health, and other medical conditions such as obesity, high blood pressure, high cholesterol, diabetes, and other common chronic diseases.
Location of Cancer in the Body
The effects of cancer on the ability to exercise or on the benefits of exercise will vary according to where the cancer occurs. For example, a woman who had breast cancer treatment likely had surgery on her chest wall. She may also have elected to have reconstructive surgery. Both of these surgeries result in changes in the way she moves her shoulders and upper body. By contrast, a colon cancer patient may have had abdominal surgery and have a temporary or permanent alteration in the manner of waste elimination, including a bag to receive feces that is worn under the clothes (called an ostomy bag). This creates a higher level of risk with regard to infection since a hole in the abdomen exposes the inside of the body. There is also a higher level of risk for a hernia. As a result, the colon cancer survivor may now relate to abdominal exercises differently and wear different exercise clothing. A prostate cancer survivor may have issues with urinary incontinence, in part due to curative surgical procedures. Urine leakage could be embarrassing. An exercise plan minimizing activities that would increase leakage (e.g., jumping activities) might be desirable. Finally, a sarcoma survivor with a missing foot (and likely a prosthesis) would appreciate an exercise plan that accounts for the changes in balance and stability that have occurred due to limb amputation. In each case, these changes should not be taken as grounds not to exercise. Instead, the changes are reasons an exercise program needs to be individualized.
Body Systems Affected by Cancer and Treatment
Many of the changes that occur are a result of the surgeries undertaken to remove cancer. Adjuvant cancer treatments, such as radiation and chemotherapy, can also have adverse effects. These effects influence the ability to exercise as well as the benefits.
Adverse Effects of Radiation
Ionizing radiation continues to damage the specific area of the body that was treated for the remainder of life. Radiation techniques are changing and improving the “scatter” radiation that affects healthy tissue, but adverse effects continue to be documented. The effects are localized to the part of the body that received radiation. If radiation was received on the chest wall, it may cause damage to the heart and lungs. Development of arrhythmias (changes in heart rhythm) is the most common radiation-associated adverse effect with regard to the heart. Pulmonary fibrosis can also occur due to radiation to the chest wall. Radiation lower on the torso may result in gastrointestinal changes, including irritable bowel syndrome. Damage to soft tissue continues as well, which can result in stiffness and altered range of motion in the area that received radiation. For example, breast cancer survivors may find that they become tight (less flexible) on the side of the upper body that received radiation. The encouraging news is that exercise can be helpful for this issue.
Adverse Effects of Chemotherapy
Unlike what occurs with radiation, the effects of chemotherapy are systemic and thus the adverse effects may affect multiple body systems. The specifics of body systems affected and the nature of the changes vary according to the class of chemotherapy drugs. For example, anthracyclines are a class of drugs commonly used for breast cancer that can damage the heart, increasing risk for cardiomyopathies and heart failure. By contrast, all of the chemotherapy drugs that are platinum based (with names that end with “-platin”) cause peripheral neuropathy (i.e., damage to nerves that can cause weakness, numbness, and pain) that may be permanent. Knowing what chemotherapy drugs were used in your treatment is important so that you can be aware of the adverse effects that might be associated with those drugs. Knowledge is power: Knowing what the possible adverse effects are allows you to know when to speak up with your doctor to ask for screening or treatment. Table 14.3 provides more details on these effects and whether there is evidence that exercise can help with the issue (8, 11, 14, 15, 16).
Influence of Medications
A broad variety of medications are prescribed to cancer patients and survivors that may affect both the ability to exercise and the potential benefits of exercise. Since reviewing all possible options is beyond the scope of this chapter, consider this general advice that applies to all cancer survivors: Ask your doctor and pharmacist what effects your medications have on the body beyond the purpose for which they were prescribed. Ask whether the medication will alter your ability to exercise safely or the likelihood that exercise would be beneficial. If there are body systems affected by your medications, be aware of any changes you experience in your ability to exercise or in how your body adapts to the exercise. And as always, start slowly, progress slowly, and let your symptoms guide you.
Q&A
Can exercise really help following chemotherapy?
Problems sleeping and persistent tiredness are common. Although it seems counterintuitive, a program of aerobic activity helps with fatigue. In addition, yoga has benefits for sleep outcomes in cancer patients, as well as the expected benefits for balance and muscular fitness. Consult with your health care provider for recommendations on local programs specifically designed for cancer survivors (e.g., YMCA or hospital-based fitness centers).
There is compelling scientific evidence that exercise is safe and beneficial for those on a cancer journey, from the point of diagnosis through to the balance of life. There was a time when cancer doctors would tell their patients to rest, take it easy, and not push themselves. More recently, that advice has changed. Three major national organizations have issued guidance that cancer survivors should avoid inactivity and exercise regularly, both during and after treatment. Survivors who do so can experience improved physical function and quality of life, among other benefits.