What is it?
Cancer related fatigue is the most common side effect reported by cancer patients during or after chemotherapy or radiotherapy treatment, occurring in up to 70% of patients. It can be defined as a feeling of weariness, tiredness or lack of energy that varies in severity. It is not alleviated by rest or sleep. This symptom can have long-lasting effects, commonly persisting for years after therapy has ended.
Why does it happen?
Cancer and its therapy can cause various changes in the body that detrimentally affect the body’s ability to supply oxygen to the cells. An impairment in oxygen delivery results in reduced energy production needed to perform work. This may cause the fatigue characterised by unusual exhaustion when performing normal daily activities, as well as lethargy and mental fatigue including lack of concentration or loss of memory.
- Chemotherapy can damage bone marrow which impairs production of red blood cells.
- Impaired muscular function (muscle wasting and weakness) is a common result of cancer and its treatment.
- Deconditioning due to inactivity/bed rest can decrease metabolic enzymes which lead to further muscle wasting.
- Decreased energy production due to above mechanisms which leads to excessive fatigue with a low level of exertion.
What effect does exercise have?
Traditionally, the recommendation has been to rest and avoid physical effort in an attempt to avoid worsening of fatigue related symptoms. However, there is a growing body of evidence that exercise can prevent the onset of, and reduce the severity of cancer-related fatigue. Evidence shows that regular aerobic exercise at a targeted intensity can significantly reduce the severity of cancer related fatigue for individuals during and post cancer therapy.
Resistance training is beneficial in preventing loss of muscle mass, which may offset muscle wasting, which often occurs as a result of cancer treatment and prolonged bed rest. Therefore resistance training may assist in preventing or reducing the severity of cancer-related fatigue. Regular exercise can also have a number of secondary benefits such as increased feelings of control, independence and self-confidence, and a reduction in feelings of fear and anxiety or social isolation.
Evidence also suggests physical activity and exercise is safe and well-tolerated by cancer patients. Exercise Physiologists can develop a safe and individualised exercise regimen that will take into account existing co-morbidities and severity of fatigue.
Over the last 10 years, we have helped over 35 patients undergo appropriate exercise during their cancer treatment. Each of them state how exercise was the biggest help through the process. Thankfully not one of these patients lost their life to this disease. These testimonies are some of the most positive reasons why you should encourage anyone to undergo this program if they are suffering from this disease.