Fittler has revealed how he felt compelled to turn his life around after the lowest point of an otherwise glittering career left him feeling empty.

It was just after the turn of the century when not even a premiership, a Rothmans Medal, a Golden Boot and more than 60 games for his state and country were enough to keep the critics at bay.

"I just needed to change. I had this ripping year in 2000 and the year after was just an absolute dud," the NSW State of Origin captain told AAP on Tuesday.

"In 2000, I got the Golden Boot for best player in the world and 2001 I was the most over-rated player in our game in one of the polls.

"That was enough to say that something had to change."

So Fittler, the one-time party boy turned environmentalist and humanitarian, sought salvation from Father Chris Riley, who opened a new chapter in the league legend's life.

It only took one nightly street walk with Father Chris to open Fittler's eyes.

"You just cruise around, chat with people if they wanted to have a chat and there were opportunities to sit there and eat with them and all that sort of stuff. It was a massive eye opener and that just turned things around," Fittler said.

"Me and a friend came up with the idea; we just needed a change of direction and it ended up a great idea."

Having traded bourbons for herbal tea and ditched nights out in favour of early-morning yoga sessions, Fittler said for all rugby league had given him he still felt a void in his life before deciding to give back.

"I know a few blokes who have done something similar - (Anthony) Watmough. It's a great way to change your perception and change your energy," he said after handing over a cheque for $60,000 to Father Chris's Youth Off The Streets program.

The money was raised when Fittler and fellow Blues greats Danny Buderus, Steve Menzies and Nathan Hindmarsh embarked on their 2019 Hogs For The Homeless tour.

"Now anything I ever do is based around trying to give first and the rewards always come from that.

"You give and then you work hard and then everything turns out alright. So that's pretty much the motto these days."

Fittler often takes his own two teenage children to see Sydney's homeless to offer them similar perspective.

"I'm actually doing a trip out to Burke and Brewarrina and Walgett next week and taking them out," he said.

"I just try as much as possible to give them an insight into the reality. As long as they understand the reality then they can choose their own path.

"As long as they know everyone gets it a little bit different."

Australian Associated Press