Cancer patients should be encouraged to take part in physical activity both during and after treatment, according to new guidelines from the American College of Sports Medicine (ACSM), US.

The recommendations have been published following a review by a 13-member panel of ACSM experts into the safety and benefits of exercising while receiving cancer therapy.

Cancer sufferers previously advised to avoid physical activity are now being encouraged to take part in up to 150 minutes of exercise each week, including swimming, yoga and strength training.

Although the research found that "most types" of exercise can benefit patients, doctors are being advised to tailor programmes to cater for individual fitness levels and safety requirements.

Kathryn Schmitz, associate professor of epidemiology and biostatistics and a member of the Abramson Cancer Centre at the University of Pennsylvania's School of Medicine, led the ACSM panel's research.

Schmitz said: "We have to get doctors past the ideas that exercise is harmful to their cancer patients. There is a still a prevailing attitude out there that patients shouldn't push themselves during treatment, but our message - avoid inactivity - is essential.

"We now have a compelling body of high quality evidence that exercise during and after treatment is safe and beneficial for these patients, even those undergoing complex procedures such as stem cell transplants."