Ellison (34), who is still playing in Japan, was in Dunedin over the weekend taking a coaching clinic for promising secondary school players.
The clinic outlined skills both on and off the field if players were thinking about a future in the sport.
Ellison, who played for four Super Rugby teams - Blues, Hurricanes, Highlanders and Rebels - said times had changed from when he was a promising, up-and-coming player.
''What is surprising me a wee bit is just the age everyone is starting to think about a career as a professional player,'' he said.
''It used to be in your last couple of years of college you might be playing well and thinking maybe I can get into an academy somewhere. But now at the college, in the first year, it's into a programme.
''That is great but they have to provide that education around that. If they [pupils] can play rugby well then, hopefully, they will get support in other areas of their lives.''
Ellison, who played for the Highlanders in 2012-13, said it was not just the physical lessons but also the mental side of the game which was important.
School players should still play the game as a game first and foremost.
''At times it does become like a job ... and if you are now starting 10 years earlier, when are you going to be burnt out? That is the question I ask.''
Ellison said there was only so many places in a Super Rugby squad in New Zealand and competition was incredibly tough.
''You're probably only looking at 5% to 10% of the players making it.''
He said young players needed to be educated concerning the game, and to ask older players questions and seek help when they need it, which was what he was trying to do.
Ellison, who is married with four children ranging in age from 1 to 8, is still turning out for the Ricoh Black Rams in Japan.
''We had a good year last year. I'm back playing at first five, and really enjoying it. I'm looking forward to getting back up there again this year.
''I've just turned 34 so I'm going to keep going. I'm playing well so I'm enjoying it or am I enjoying it because I'm playing well. It might be the other way round.''
The utility back is helping his club Norths out when he is home in Wellington along with his younger brother Jacob, who turned out for Otago and the Highlanders in 2012. Jacob, a prop, is also playing in Japan.
Ellison played 23 games for the Highlanders in 2012-13 and the franchise tried to get him back in 2014 after he signed to head to Japan.
The Highlanders were turned down by New Zealand Rugby and, in a clear example of one door closing creating an opportunity for another, the Highlanders signed Malakai Fekitoa from Auckland as Ellison's replacement.
The four-test All Black said the family had enjoyed their time in the South.
''When I had gone there to play a game with the Hurricanes you didn't really see anything of Dunedin. Just play the game and leave.
''But we really liked it down there. The more you travel around the world the more you appreciate places like Dunedin.''
