Washington ? Cancer survivors, better work up a sweat.

New guidelines are urging survivors to exercise more, even — hard as it may sound — those who haven’t yet finished their treatment.

There’s growing evidence that physical activity improves quality of life and eases some cancer-related fatigue. More, it can help fend off a serious decline in physical function that can last long after therapy is finished.

Scientists have long advised that being overweight and sedentary increases the risk for various cancers. Among the nation’s nearly 12 million cancer survivors, there are hints — although not yet proof — that people who are more active may lower risk of a recurrence.