The 36-year-old told more than 100 students at Canberra's Institute of Technology on Wednesday how he battled a gambling addiction during his 15-year NRL career.

Once, he said, he spent $10,000 in winnings in days – easily.

The problem was that as an NRL star he could afford it. But he was uncomfortable with it, and he hid the problem from the people he knew.

"It wasn't until I told [people] that things started getting easier," he told the group.

"If you want to ask for help, it's OK to do that. We're changing as a society, so it's OK to put your hand up, it's OK to ask your mate beside you, 'You OK? Everything all right in life? You got control of things?'

Hindmarsh is now a ClubSafe ambassador, brought to Canberra by ClubsACT.

He never uncovered why his was drawn to gambling, but in response to a question agreed it was probably a cultural problem within the NRL when he was playing.

"I used to watch a lot of the senior guys, I was at the airport one day, and they're betting on whose bag came out of the carousel first. I reckon there was that, a bit of the beer-drinking, gambling culture which didn't help my situation. The access to money, and the no questions asked, didn't help."

But he believed things had changed since then, and players were more educated.

Apprentice carpenter Isaac Struss, 27, who watched Hindmarsh speak, said he knew many people who had and still were battling gambling addictions.

"It's good that someone can come have a chat to everyone about it, and get people thinking about their issues," he said. "I've seen it before, it can happen to anyone."

Peter Hansen, director of trade skills at CIT, said gambling appeared to be ever-present, including online and on television, and all young people could be vulnerable.

"I probably wouldn't identify trade students alone [as vulnerable to gambling addiction]. I think anyone that's young, and growing up. I mean, there's just so much out there and it's so easy to get access."