An inactive lifestyle increases the risk developing kidney or bladder cancer, according to a US study.

Researchers at Roswell Park Cancer Institute in Buffalo, New York, studied 160 patients with renal (kidney) cancer, 208 with bladder cancer and 766 people of the same ages who did not have cancer.

A team led by Dr Kirsten Moysich and Dr Rikki Cannioto surveyed the participants to find out whether lifetime sedentary behaviour was associated with risks of developing either of the cancers.

Physically inactive individuals were those who said they had never taken part in any regular or weekly recreational exercise throughout their lifetime. Physical active participants were those who reported at least some regular weekly exercise throughout their lifetime.

The study, published in Cancer Epidemiology, showed that those who were physically inactive were 77 percent more likely to develop renal cancer and 73 percent more likely to develop cancer of the bladder.

The authors found similar risk exposure among both obese and non-obese participants, suggesting that the connection between inactivity and these cancers is not driven by obesity.

Dr Moysich, the study's senior author and professor of oncology in the departments of Cancer Prevention and Control and Immunology at Roswell Park, said: “We hope that findings like ours will motivate inactive people to engage in some form of physical activity.

“You don’t have to run marathons to reduce your cancer risk, but you have to do something — even small adjustments like taking the stairs instead of the elevator, walking around the block a couple of times on your lunch hour or parking the car far away from the store when you go to the supermarket.”

The US Department of Health and Human Services recommends 150 minutes each week of moderate physical activity or 75 minutes each week of vigorous physical activity.