Taeyoung Lee crossed the finish line at Ironman Korea in Gurye, South Korea, on Sunday, September 28, 2025, raised six fingers, and cried for 15 minutes. He was 21 years and 167 days old. He had just become the youngest person to complete a full Ironman triathlon on six continents.

Guinness World Records confirmed the record on October 20, 2025. Northwestern announced the recognition on July 15, 2026, after Lee graduated from the McCormick School of Engineering with the Class of 2026. He earned his degree in computer science while training roughly 14 hours per week and living on shrimp and unseasoned pasta to save money, according to Northwestern Magazine.

A full Ironman covers 140.6 miles: a 2.4-mile swim, a 112-mile bike ride, and a 26.2-mile marathon. Lee completed six of them in 11 months, spanning Arizona, New Zealand, South Africa, Brazil, Sweden, and South Korea.

The speed of his progression is staggering. Lee joined Northwestern's Triathlon Club as a sophomore after his fitness had slipped during his first year on campus, training at Henry Crown Sports Pavilion and The Garage. He finished his first Olympic-distance triathlon in May 2024, his first half-Ironman in September 2024, and his first full Ironman in Tempe, Arizona, on November 17, 2024. He had never run a marathon before that day. The entry fee alone cost $1,002.66.

"I saw this article about this 26-year-old from Canada," Lee told The Daily Northwestern in January 2026. "He broke the world record for being the youngest person to do an Ironman on six continents, right? And then I thought to myself, 'Wait, I could do this.'"

The previous record belonged to Connor Emeny, who completed the feat at age 26. Lee beat it by nearly five years.

Not every race went smoothly. In New Zealand on March 1, 2025, Lee's gear box containing his bike, wetsuit, and running shoes never arrived. He spent his rest day scrambling for replacements and still finished in 12 hours, 12 minutes, and 57 seconds. Just 29 days later, he completed Ironman South Africa in his slowest time of the quest: 13 hours, 9 minutes, 50 seconds.

After New Zealand, fellow Northwestern Triathlon Club member Hayden Sikora, a 2024 Communication graduate, reached out to coach Lee. Sikora shifted Lee's training away from long runs toward sprint work. The change paid off. Lee posted his fastest time in Brazil on June 1, 2025, at 10 hours, 46 minutes, 10 seconds, then beat that personal best in South Korea with 10 hours, 43 minutes, 21 seconds.

For the Sweden race on August 16, 2025, Lee's entire family traveled to Kalmar: father Hoi Chang, mother Hwa Yong, and brother Daniel. It was the only race they attended in person. "It was a really good memory for me," Hoi Chang told North by Northwestern. "Whole family was there and waiting at the finish line."

Lee was born in South Korea and moved to the United States at age 3. He chose to study abroad in Seoul during fall quarter 2025, putting his final weeks of training on Korean soil before the record-setting race in Gurye, where his aunt, grandmother, and study-abroad friends cheered him across the line.