Sam Long (born December 23, 1995) is an American professional triathlete.

Long was born prematurely as one of three triplets in Boulder, Colorado, and grew up mountain biking and swimming with his parents.

He competed in his first Ironman at the age of 17, prior to attending the University of Colorado, where he graduated with a double major in psychology and physiology.

In 2021, he finished second to Gustav Iden at the Ironman 70.3 World Championship in St. George, Utah.

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