There is a 1 in 2 risk of any Australian being diagnosed with some form of cancer by the time they reach their 85th birthday and a 1 in 5 risk of them dying from the disease. With statistics, such as these, it’s evident why the effects of cancer are so widespread. If it doesn’t affect you personally, it will without a doubt affect a family member, friend or loved one.
Historically, cancer patients were told to rest and take it easy, with consensus being that they were too sick to exercise. However, with evidence supporting the many benefits of physical activity, it is now clear that they are too sick NOT to exercise!
Exercise and Cancer Prevention
It has always been said that prevention is the best form of cure. While we know that cancer is a cruel disease that doesn’t discriminate, it is possible to lower the risk of developing some forms of cancer. It is estimated that more than half of all forms of cancers are potentially preventable through healthy lifestyle choices and regular screening. The recommendations are to try to perform 150 minutes of physical activity per week (approximately 30 minutes per day) but also to avoid sedentary behaviours (e.g., extended periods at computer, watching television, etc.)
There is convincing evidence that having a higher amount of fatty tissue in one’s body causes a higher risk of developing various forms of cancers, including breast (post-menopausal), colorectal, oesophageal, endometrial, pancreatic, kidney and liver cancers. Studies also showing higher levels of body fat is a probable contributing cause of gallbladder, advanced prostate and ovarian cancers. Exercise, of course, is one of the most effective methods of decreasing body fat, in conjunction with a calorie controlled diet.
Looking at exercise specifically as a preventative tool, there is sufficient evidence to state that meeting physical activity guidelines decreases the chance of developing some types of cancer (post-menopausal breast, colorectal and endometrial) and it is likely that it may also help protect against pre-menopausal breast, lung and liver cancers.
There are early results that show a link between increased physical activity levels and decreased risk of developing some forms of aggressive prostate cancer, thought to be due to weight loss resulting from exercise.
Further research is still to be done but many early signs demonstrate a positive correlation between exercise and cancer prevention.
Prehabilitation
Every year football teams go through tough preseason training to prepare for the season ahead. They build up cardiovascular fitness and muscle strength, as well as identify any potential weak spots and limitations. Cancer patients can also undertake their own preseason training, known as “prehabilitation.” During the time between diagnosis and the beginning of active treatment there is an opportunity to build up physical fitness and energy stores, in an attempt to decrease treatment related side effects.
Prehabilitation usually consists of exercise along with nutritional guidance and psychological assessment and support.
Patients having to undergo surgery as part of their treatment often find they get better outcomes and have a smoother recovery if they have done some prehabilitation, and many anaesthetists also recommend it to decrease the risk of surgical complications.
Treatment
Some patients or their carers are fearful of exercising during cancer treatment; however, it is widely accepted among the medical profession that exercise is generally safe during treatment, although it is recommended that it is done under the guidance of a qualified health professional (e.g., an exercise physiologist or physiotherapist). With the correct instruction, physical activity can be used to help combat many common side effects of cancer treatment.
1. Maintaining a Healthy Weight
In cases where patients are losing weight due to treatment, exercise helps to maintain muscle mass and prevent sarcopenia (a form of muscle wasting). It is important to incorporate light resistance training especially for the legs.
Contrary to popular belief, a large proportion of cancer patients gain weight during their treatment due to inactivity or as a side effect of medication. Steroids cause fluid retention and increase appetite and patients sometimes report emotional eating leading to weight gain. Exercise helps to limit weight gain by increasing calorie expenditure. Of course, in any attempt to lose weight, nutrition also plays an incredibly important role.
2. Mobility and Joint Pain
Many patients report feeling “off their legs” as a result of cancer treatment, usually due to more time spent in bed. Inactivity can result in muscle weakness especially in the legs and core muscles. Some medications, such as aromatase inhibitors, used in the treatment of breast cancer can also cause joint stiffness.
Stay mobile by going for a gentle walk first thing in the morning when you’re feeling most energised and try to perform gentle movements spaced throughout the day. Do leg strengthening exercises while sitting in your chair or go for a walk around the living room during the ad breaks on TV. Keeping active also helps prevent back pain by helping to maintain strength in the core muscles, which provide support for the spine. Be mindful of having correct posture when standing or sitting and try not to slouch or slump on the couch.
3. Fluid Retention / Lymphoedema
This condition is characterised by a build-up of protein rich fluid (known as lymph), usually seen in the arms or legs. The build-up occurs due to congestion after the lymphatic system is interfered with – either during surgery where lymph nodes are removed or when the lymph nodes are infiltrated by disease or infection (which damages the lymphatic vessels). Breast cancer patients are the most well-known sufferers of lymphoedema; however, it can affect any cancer patient.
Historically, patients were encouraged to rest their affected limb, yet research has shown that not only is exercise safe for lymphoedema, but it is quite helpful for the prevention and treatment of the condition. When exercising, ensure that you are wearing a properly fitted compression garment and avoid repetitive loading of the affected limb. The best form of exercise is resistance training with light weights as the movement creates a ‘muscle pump’, which helps to facilitate lymphatic fluid return.
Patients may also retain fluid for other reasons. Usually observed in hands and feet, non-lymphatic fluid retention can be caused by the use of certain medications or by the heart, liver or kidneys not functioning adequately. Poor nutrition can also be a factor in this type of fluid retention. Resistance training can be used in the same way as lymphoedema to try to increase the muscle pump mechanism and return the fluid back to the central portion of the body.
A physiotherapist will usually be the best person to guide you through the best strategies to manage fluid retention.
4. Osteoporosis
A side effect of some cancer treatments is decreased bone mineral density which can lead to osteoporosis (or its precursor, osteopenia). Osteoporosis results in an increased risk of bone fracture, either through impacts / falls or a crush fractures which can be seen in the bones in the spine if they weaken substantially. Most patients who are at risk of osteoporosis are placed on medications known as bisphosphonates, which can be quite effective in limiting deterioration of the bones. However, it is recommended that patients also participate in weight bearing exercises to facilitate bone strengthening. Balance training is also advised to prevent falls. Combination exercise programs, such as Tai Chi or Yoga can provide the perfect mix of weight bearing and balance.
5. Prostate Cancer and Exercise
The most commonly diagnosed cancer in men deserves a section of its own. Generally, a slow growing disease, prostate cancer has good survival rates if treated appropriately and promptly. However, high grade disease can spread very quickly. Exercise has been shown to slow the rate of disease progression by 57% and reduce recurrence / mortality by 30%. Some cases of prostate cancer are assessed as slow growing and they are not deemed suitable for treatment; these can be managed by exercise and surveillance alone.
6. Fatigue Management and Sleep
One of the most commonly reported symptoms in cancer patients, fatigue can be debilitating and make it incredibly challenging to complete activities of daily life. It is a well-known side effect of both chemotherapy and radiotherapy, and it is often at its worst after treatment has finished, lingering for several weeks.
Contrary to popular belief, physical activity doesn’t worsen fatigue – in fact, it helps to increase energy levels and improve sleep quality. Exercise may seem daunting, but can the suggested daily 30 minutes of activity can be broken up into manageable loads. Learning to subdivide and ‘pace’ activities can help patients avoid becoming too exhausted.
7. Breathlessness and Secretion Clearance
Whether it’s due to deconditioning, disease or treatment side effects, breathlessness can be one of the most limiting symptoms of cancer.
It may seem counterproductive for a patient to exercise to the point of feeling out of breath, yet this is the best way to improve the efficiency of the lungs and respiratory muscles. If the lungs are never challenged, they become more deconditioned, further worsening the symptoms of breathlessness.
Exercise is also helpful to clear the mucous that can build up in the lungs and airways. By taking bigger breaths, which happens naturally when you’re physically active, air can move behind the secretions and help to shift them upwards to a point where it’s easier to cough and clear them.
It is recommended that patients focus on aerobic exercise of moderate intensity. Split your activities in smaller sections and find a couple of positions that are effective for catching your breath.
8. Cardiovascular Health
It’s unfortunately the case that chemotherapy agents can cause damage to the heart and lung tissue. Patients will typically have echocardiograms at regular intervals throughout their chemotherapy treatment to monitor their cardiac function. Exercise can help to limit damage to the heart muscle by improving its efficiency at pumping blood around the body to and from the muscles.
Cardiovascular health can also be affected by general deconditioning from inactivity during treatment, which is similar to losing fitness after an injury or even a holiday. Therefore, it’s recommended for patients to remain as active as possible during treatment even if small doses are all they can tolerate.
9. Peripheral Neuropathy
Neuropathies are characterised by pins and needles or numbness usually felt in the fingers and/or toes and, in a cancer context, these often occur due to chemotherapy agents irritating the nerve endings. Peripheral neuropathies can affect fine motor skills, such as doing up buttons and writing, or cause balance problems due to poor sensation in the feet. Frustratingly, nerves can be incredibly slow to recover; patients may continue to see gradual improvement for up to two years.
To help treat a peripheral neuropathy, continue to practice fine motor skills and balance training if lower limbs are affected. The more you use your hands and feet, the more the nerves are stimulated. Take extra care of hands and feet by wearing appropriate footwear, checking for blisters, cuts and scratches and ensure that you avoid extreme temperatures.
10. Improved Mood
One of the less visible side effects of cancer treatment is low mood and depression. During exercise, hormones known as endorphins and serotonin are released from the brain which result in improved mood. Indeed, exercise is so effective that it is now prescribed specifically as a treatment for mental health conditions.
Get active, get outside and benefit from the Vitamin D and even better, get social and exercise with others for the best method of natural anti-depressant.
Survivorship
Once treatment has finished and if patients are fortunate enough to go into remission, they enter a phase commonly referred to as “survivorship”. During this time exercise continues to have significant benefits. Various side effects can persist to be a factor long term, some unfortunately never resolving.
1. Decreased risk of recurrence
Those who have survived cancer treatment can decrease the risk of disease recurrence by ensuring that they meet the recommended target of 150mins of exercise per week. This has been proven by research in bowel cancer and breast cancer patients, the latter in which their risk of recurrence decreased by 24%.
2. Decreased risk of mortality
If recurrence does unfortunately occur, there is a growing body of evidence that suggests that physical activity can reduce cancer patients’ chances of dying from the disease. Breast and prostate patients can lower their risk by 30-40% if they meet the 150 minutes of exercise goal and bowel cancer patients can reduce the risk by up to 50% compared to those who don’t exercise.
3. Regaining control and returning to normal life
Patients often report feeling apprehensive about finishing treatment. They’re ecstatic to have it completed, however they then feel cut off from the nurses, doctors and other health professionals who have been their support network for so long. There is also then the worry about whether the disease will return. By focusing on an exercise program, survivors can take control of their health and refocus their energy on something positive. They can potentially meet a new network of people in sporting groups and throw away the label of being a “patient.”
4. Look good and feel better
The aesthetic effect of exercise is one of the most tempting in all populations, not just cancer patients. Treatment can cause hair and nails to fall out, weight gain and muscle wasting, as well as fluid retention and skin changes. While exercising might not be able to solve all these problems, it can certainly contribute to improving the condition of your skin, body composition and enhancing self-confidence.
More research is being done every day on the value of exercise for cancer patients and there seems little doubt that the known benefits will continue to accrue. Remember, though, that the information in this article is general in nature and not medical advice. Patients should enlist the help of a health care professional, such as a physiotherapist or exercise physiologist, who is experienced in cancer care.
