Cancer survivors are at greater risk of recurrence because they are not physically active enough, Macmillan Cancer Support has said.
Traditionally cancer patients were told to "rest up" after their cancer treatment and to "take it easy", yet the health charity's report, Move More, discovered physical activity is key to the recovery and long term health of cancer patients.
It found breast cancer patients' risk of recurrence can be reduced by up 40% through physical activity.
For those with bowel cancer or prostate cancer the figures are 50% or 30% respectively.
After treatment all cancer patients can reduce their risk of getting side effects of cancer and its treatment through physical activity. These include fatigue, depression, osteoporosis and heart disease.
Yet Macmillan said many health professionals are not aware of this, with the majority not talking to patients about exercise.
Over half (56%) of GPs, practice nurses, oncologists and cancer nurses do not speak to their patients about the possible benefits of physical activity, or at best they speak to just a few of them. This rises to 72% of GPs and 60% of oncologists.
Ciaran Devane, Chief Executive of Macmillan Cancer Support said: "It is essential that physical activity services are available and ‘prescribed' to all cancer patients.
'Cancer patients would be shocked if they knew just how much of a benefit physical activity could have on their recovery and long term health, in some cases reducing their chances of having to go through the grueling ordeal of treatment all over again.
'It doesn't need to be anything too strenuous, doing the gardening, going for a brisk walk or a swim all count.
