He won his first Full Contact Karate competition in 1976 after only six months of training under the direction of John Therien (who now holds Hanshi degree in Ju-Jitsu),[citation needed] and subsequently became Canadian middleweight kickboxing champion two and a half years later.
He was referred to as "The Iceman," a nickname given to him by Rodney Batiste during his first title defence, due to his intimidating icy stare and cool demeanour in the ring.
[3] Thériault has a number of high-profile victories, including two wins against future four-time K-1 champion Ernesto Hoost and a draw against the legendary Don "The Dragon" Wilson.
[citation needed] Since his retirement on December 1, 1995, (a third-round knockout of Marcus Reid) Thériault still trains five days a week and teaches classes at Therien Ju-Jitsu & Kickboxing Schools.
With the aid of his friend Hanshi John Therien, he is giving young fighters an opportunity in the "Iceman Amateur Kickboxing Circuit".