Thériault began his martial arts training in 1972 at age 17,[1] achieving blue belt status in Jujutsu before becoming interested in Karate and Full Contact Karate a few years later. 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.[2] In 1980 he won the PKA Middleweight World title (Full-contact karate), and held the championship for a record of 15 years.[citation needed] He has also won world titles in both the ISKA and PKC associations. During the peak of his career, Thériault held only a yellow belt in Karate.
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. He has also fought world champions such as Rob Kaman, Tosca Petridis and Rick Roufus.
Thériault has worked with many groups and charities, such as the Big Brothers, Make a Wish Foundation - Canada, Leucan.[citation needed] He is author of a book on kickboxing techniques and has a series of videos on the science of combat sports.[citation needed] He is the subject of an hour and a half film produced by the National Film Board.[citation needed] He was voted Athlete of the Decade by the Sports Writers Association of New Brunswick.[citation needed] However, the New Brunswick Sports Hall of Fame still will not induct him into their ranks after several attempts by fans and friends.[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.
Thériault has also become a world-class promoter for the sport of kickboxing. With the aid of his friend Hanshi John Therien, he is giving young fighters an opportunity in the "Iceman Amateur Kickboxing Circuit".
Thériault obtained his Black Belt in Ju-Jitsu in early 2008.
Titles
1995 I.S.K.A. Full Contact Light Heavyweight World Champion
1992 I.S.K.A. Full Contact Super Middleweight World Champion
1988 I.S.K.A. Full Contact Light Heavyweight World Champion
I.S.K.A. Full Contact Super Middleweight World Champion
P.K.C. Super Middleweight Full Contact World Champion
1980-1995 P.K.A. Full Contact Middleweight World Champion
1978 Canadian Full Contact Middleweight Kickboxing Champion
Thériault fought 76 fights from June 1976 to December 1995. Of those fights, 69 were wins (61 knockouts), 6 were losses, and 1 was a draw.[5][6] The one draw was with Don "The Dragon" Wilson on December 18, 1984.[7] Thériault was full-contact World Champion 23 times.[8]
Fight was for Thériault's I.S.K.A. Full Contact Super Middleweight World title and Kaman's W.K.A. Full Contact Light Heavyweight World title. The I.S.K.A. title would be vacated due to Kaman coming in over the weight for the fight, although Kaman would retain his W.K.A. title.
Thérien, John (August 2005). "A talk with Kyoshi John Thérien". Your Martial Arts Resources (Interview). Interviewed by Torbjorn Arntsen. Retrieved 2009-07-18.
Kelly, Perry William (May 2006). "A talk with Perry William Kelly". Your Martial Arts Resources (Interview). Interviewed by Torbjorn Arntsen. Retrieved 2009-07-18.
