Exercise Training for Cancer Patients
Exercise training is useful for helping cancer patients to regain full health and an active lifestyle. The pathophysiology of cancer, along with its management and medications, needs to be considered when designing an exercise training programme for a cancer patient.
The Pathophysiology of Cancer
Cells with normal, healthy genes have regulated proliferation, and only reproduce when they are instructed to do so. If the genetic control of a cell becomes abnormal, the cell can break free from the normal restraints on its growth. This leads to abnormal enlargements of tissue known as tumours, which may be benign or malignant. Benign tumours are not cancerous and remain localised, but malignant tumours are cancerous and can spread to other sites in the body.
It is the tendency of malignant tumours to spread and grow that makes them dangerous. If the spread remains untreated, cancer cells can invade and destroy vital organs -- this is how cancer kills. Cancer often spreads via the circulatory system.
Management and Medications for Cancer
Most current cancer treatments aim to combat uncontrolled growth, tissue invasion and metastasis. Surgery is widely used and is quick and effective, but it cannot treat cancer that has metastasised widely throughout the body. Often radiation therapy is preferable to surgery. This emits powerful x-rays, which irradiate the region of the cancerous tumour, and either inflicts genetic damage sufficient enough to kill cancerous cells, or induces cellular suicide (apoptosis).
Radiation sometimes fails to eradicate all cancerous cells of a tumour, and chemotherapy must be used. Chemotherapeutic drugs travel throughout the body via the blood circulatory system, but used alone often cannot cure cancer. Therefore a programme of care often involves a combination of all three methods of treatment.
Cancer Treatment Side Effects
Cancer treatments are often successful but they are not without side effects, the most common of which are:
- Pain, loss of flexibility, amputation, damage to sensory and motor nerves -- associated with surgery
- Loss of flexibility in joints, cardiac and lung scarring -- associated with radiation
- Peripheral nerve damage, cardiomyopathy, pulmonary fibrosis, myopathy -- associated with chemotherapeutic drugs
Someone who is receiving a combination of anti-cancer treatments may experience a number of side effects. There are some side effects of anti-cancer treatments that can be acute, including anaemia and fatigue, as well as inflammatory response in lung tissue and impaired oxygen transfer caused by radiation.
Exercise Testing for Cancer Patients
Exercise training is useful in aiding a cancer patient's rehabilitation and recovery, and it is important to tailor an exercise programme specifically to the individual's needs. Exercise testing will help to determine these needs by measuring the patient's aerobic, strength, flexibility and functional capabilities as well as assessing the extent to which they are limited by any side effects of treatment.
It is important that formal exercise testing is individualised according to the type of cancer and malignancy, as the effect of cancer on the patient's functional ability can be profound. For example, patients with advanced lung cancer can experience severe breathlessness during physical activity. The patient's pain threshold also needs to be taken into account, as certain types of activity can cause them extreme discomfort.
Cancer treatment-related fatigue is a common and disruptive side effect of chemotherapy. Exercise testing in these circumstances will determine whether low-level protocols are required during an exercise-training regime.
Exercise testing is not only useful in assessing the effects of complications that may arise from different malignancies and therapies, but it will also reveal other co-morbid conditions such as coronary heart disease, high blood pressure, diabetes and high blood lipids which may influence exercise management.
Exercise testing should be continued throughout the patient's training and rehabilitation to help monitor their progress.
Exercise Training Programmes for Cancer Patients
The point of exercise training for survivors of any type of cancer is to restore their formal level of physical and psychological functioning. Exercise training is useful in maintaining endurance, strength and level of function in people who are undergoing therapy for cancer.
As with any exercise programme, modifications are necessary to suit the individual patient's mode of treatment and the state of their disease. In particular, patients may have drug-induced cardiomyopathies which place limitations on their cardiovascular function, and in all cases the recommendations for intensity, frequency and duration should be followed with caution.
Even though anti-cancer therapy may lead to limited cardiovascular function, exercise training can still be beneficial. Most patients are affected by reduced strength and endurance, so it is logical that exercise aims to improve these parameters, but patients also experience psychological distress. Cancer patients receiving chemotherapy who follow an exercise programme during hospitalisation can significantly improve their psychological status.
Physical and occupational therapy, walking, and strength and flexibility exercises may be the most appropriate options for people still undergoing chemotherapy. Studies have shown that referred and monitored exercise is an effective and safe activity that reduces symptoms and facilitates adaptation to cancer diagnosis and treatment.
The copyright of this article is owned by Sharon Kirby. Permission to republish this work must be granted by the author.