Spencer Smith is a British triathlete who won ITU Triathlon World Championships in 1993 and 1994.

Smith moved on from short course Olympic-distance racing to long course and has competed in a number of full Ironman and half-iron distance races following his short course career.

He finished 5th at the Ironman World Championship in Kona, Hawaii, in 1998, and 8th in 2000.

During the Court of Arbitration for Sport hearing in New York it was found that the Los Angeles testing laboratory had made an error.

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