Meet Hiromu Inada, an 86-year-old triathlete. Last year, he became the oldest person to complete the Ironman World Championship.

The event is considered the toughest triathlon. It comprises a 4-kilometer swim, a 180-km bike ride and a 42-km run, totaling 226 km. Inada took 16 hours, 53 minutes to achieve the feat.

His training starts early. First, he swims for about an hour with breaks in between. Then he trains on the bike along with Olympians and Paralympians for around one hour. Finally, he runs between 2 and 5 km. He goes through this regimen 3 to 4 times a week. But Inada wasn’t always this way. He only began swimming at age 60.

Learn all about this tough old dude by watching the video above!