Junk food advertising at community clubs is undermining the benefits of children’s sport, according to a study.

The extent of the problem is staggering, says Bridget Kelly, lead author of the study published in the The Journal of Science and Medicine in Sport.

She says children are being exposed to unhealthy messages for up to four hours a week.

This is achieved through marketing on uniforms, signage on the field, discount vouchers and other promotions.

Those playing outdoor cricket and rugby league have the greatest exposure, according to the study, which was conducted in NSW but highlights a national problem.

“It is deeply concerning to see such a high frequency of fast food and sugary drink sponsorship at local sports clubs,” says Dr Kelly of the University of Wollongong.

Children’s exposure to unhealthy food and drink marketing is recognised as a significant contributor to childhood obesity, she says.

“If we are serious about tackling Australia’s childhood obesity epidemic, we need to limit children’s exposure to these unhealthy messages, particularly in environments such as community sport.”

Nearly two thirds of Australian children participate in organised sport, she says.

Nello Marino, CEO of Sports Medicine Australia, acknowledged the financial pressures faced by clubs, but expressed concern about the amount junk food advertising.

“People should show some discretion, particularly with high-fat, high-sugar products.”