Thorn, 35, will represent his country for the 42nd time when he lines up against the Wallabies on Saturday, and has been involved in the sport from a young age.
“I’ve been doing it since I was six years old,” Thorn said. “This is what I do, what I’ve always done.
“I just love it but obviously I’m going to do something else, it’s going to be interesting.”
Thorn began his career as a Brisbane Broncho in the NRL, before switching codes in 2001.
Having previously represented Australia in league rugby, he progressed through the union ranks at the Crusaders before making his New Zealand Test debut in 2003.
“I did a lot of hard work from a young age doing my weights, so I’ve strengthened my body and muscles,” he said.
“As you get older your body sets as a man and it’s in a good place.
“I just wonder if young guys come into football and get injuries that trouble them as their careers go on because their bodies are out of balance.”
Whilst still playing, Thorn has been busy gaining qualifications to become a physical education teacher.
“I’ve done a couple of papers, just started,” he said.
It appears a logical fit because Thorn has certainly mastered the art of developing and maintaining his physique.
Meanwhile though, Thorn will be keen to continue plying his trade as an All Black and will be key for their chances of regaining the Tri Nations, while pushing for a successful World Cup campaign next year.
He added: “I’d really love to play next year, it’s a big one, I want to give it a heck of a whack.
“For me, playing for the All Blacks is Christmas Day every week.”
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BIOGRAPHY: Cesc Fabregas