Intro to Exercise Oncology
In Australia, 1 in 2 people are diagnosed with cancer by the age of 85, with 1 Australian being diagnosed every 4 minutes.
With increasingly effective early-detection strategies and management options - there are now more people than ever living with the effects of previous or current cancer.
What is Cancer?
Cancer is a disease defined by abnormal cell function. Cancerous cells can develop in any part of the body but most commonly appear in the breast, prostate, bowel and lungs. However, the nature of these cancerous cells is that they can invade surrounding and distant sites by spreading through the blood vessels and lymphatic systems. If diagnosis and treatment are not administered in the early stages of the disease, cancer can be life-threatening.
How can exercise help people with cancer?
Exercise is capable of a vast range of physiological benefits to those affected by cancer, such as enhanced strength, endurance and most of the benefits that which would be expected by healthy individuals. However, advancements in research and technology that allow for more targeted medicine to treat people with cancer have found there are specific symptoms that are particularly responsive to apporpaitely prescribed exercise.
Reductions in:
Duration of hospitalisation
Psychological and emotional stress
Depression and anxiety
Number and severity of treatment-related symptoms and side effects (e.g. pain, fatigue, lymphoedema, and nausea)
Sexual dysfunction
Nervous system degeneration rate and severity
Risk of cancer recurrence and mortality
Improvements in:
Muscle strength, mass and power
Quality of life
Body composition and bone health
Physical functioning and fitness
Immune function
Cancer treatment adherence
Body image, mood and self esteem
Cognition
Sleep quality
Does exercise directly affect cancer?
The benefits of movement as medicine in oncology has led Exercise Physiology researchers to look at cellular responses to exercise that might explain the improvements in survival, quality of life and treatment effectiveness.
Specifically, a lot of research has shown that regular physical activity has a protective effect against cancer and is one of the most potent preventative medicines for cancer.
This has also allowed some research to investigate how exercise can mimic the effects of pharmaceutical interventions. We definitely aren’t at a stage where a gym membership is first line cancer therapy in place of chemotherapy, radiation or surgery. However, exercise has been shown to be an effective adjuvant therapy which allows for better treatment responses as well as greater capacity to complete treatment cycles.
In addition, to all the indirect effects of exercise such as improved fitness, weight loss and enhanced muscle mass playing a role in cancer disease progression - there are independent effects of exercise that favourably alter physiology by tapping into the the following :
Cell growth regulators
Proteins involved in DNA damage repair
Androgen receptor co-activators
Regulators of apoptosis and cell cycle arrest
Hormonal systems (Testosterone, Oestrogen, Leptin, Irisin, Resistin)
Oxidative stress and antioxidant pathways
Inflammatory cascades and cell pathways
Immune system pathways (Natural Killer Cells and T-Cells)
Dosage
Like with any medicine, a specific prescription is needed to ensure that right response occurs at the right time, with the right measures in place to minimise side-effects.
Thousands of studies have investigated the specific effects of different types of exercise in aims of determining the safest and most effective dosage to elicit improvements.
For example, resistance training has a profound effect on improving strength and reducing muscle loss (amongst many other benefits), while aerobic exercise (like walking or cycling) seem to have the strongest effect on mental health and emotional symptoms.
Guidelines suggest:
Cancer patients need to be guided through an individualised exercise prescription that is specific to them, their cancer and their needs - ESSA Exercise in Cancer Position Statement
Personalised Prescriptions
There have been many studies that show there are specific outcomes in people with cancer that be achieved with the right exercise (as shown above), but what is the right exercise?
As you’d expect, there isn’t a one-size-fits-all approach to exercise oncology, as every experience of cancer from diagnosis to treatment and survivorship is different. This depends on the outcome we are trying to achieve, which is dependant on factors such as the type/location of cancer, the previous/current treatment provided, additional medical conditions as well as other personal characteristics.
In certain cancers, like those of the Breast & Prostate - some of the therapies involved in treating the disease alter hormones responsible for bone density maintenance. Therefore, one of the primary exercise treatment aims to preserve and even increase bone mineral density, without increasing the risk for falls or other fractures.
Chemo-therapy induced neurotoxicity and nerve problems/pain are a very common side effect of treatment that has good evidence to show specific types balance and sensors-motor retraining exercises can improve symptoms when applied to the right individual in an appropriate manner. While chemotherapy is blanket therm for a variety of different drugs/pharmaceuticals, the mechanisms behind the protective and therapeutic effect of exercise appear to be similar across most scenarios.
In the last few years - there have been strong links demonstrated between Bowel Cancer and Type 2 Diabetes, largely due to the effect of insulin and other metabolic growth hormones. This has led researcher to investigate exercise interventions that influence metabolic hormones to treat/manage bowel cancer by tapping into cell pathways involved with Diabetes.
Promising research has shown us that the use of high intensity interval training (acute bouts of strenuous activity interspersed with low-moderate intensity recovery periods) is not only safe but can have profound benefits to the person with cancer. There have even been high quality studies showing this type of exercise may exert a inhibitory effect on the growth and progression of cancerous/malignant cells. Along with this there have been reports of regular exercise and physical activity engagement significantly reducing the risk for developing cancer, and cancer recurrence following remission.
Collectively, research findings strongly support the anti-cancer properties of exercise through a whole range of direct and indirect physiological responses. The specifics of these effects and how they can be implemented are foundational to the knowledge of an Exercise Physiologist with a speciality in Oncology/Cancer care
If exercise is medicine for cancer patients, why aren’t Doctors prescribing it?
One US study amongst Oncologists and other managing people with cancer suggested that clinical discussions about post-treatment exercise only occurred in 55% of cases.
The reality is - quite a lot of doctors are recommending exercise or at least referring to appropriately qualified clinicians who specialise in exercise oncology. Luckily, this is becoming more and more common practice and physical activity is steadily beginning to form a vital component in the medical management of people at risk for/experiencing cancer.
Recently a position statement by the Clinical Oncology Society of Australia stated:
Exercise should be a standard component of any cancer treatment/management program with recommendations for all patients with cancer to be referred to an exercise physiologist or physiotherapist with expertise in cancer care.” (COSA, 2018)
The life changing effects of exercise should not be overlooked, and with more people living with the effects of cancer than ever before - now is the time to promote exercise and movement as medicine. With western medical advances proving the potency of exercise, as both an adjuvant and therapeutic cancer treatment option, shouldn’t we be grabbing onto this medicine with both hands?
Exercise doesn’t need to be taken too seriously, but we should take it regularly!
Overall, the broad message is clear: Exercise should be encouraged because exercise is a form of medicine. - Dr Gill Cowen, Royal Australasian College of General Practitioners
If you’d like more information on any of the information above or would like a better understanding of how movement can be medicine for you, keep an eye out for more content like this or get in touch for a personalised plan of action today.