At age 10, Phelps held a national age-group record in which event?

At age 10, Michael Phelps held a national age-group record in the 100-meter butterfly. The achievement showed that his unusual talent was already visible long before he became an Olympic champion.

Phelps set the mark in 1995, when he was competing in the United States’ age-group system. The 100-meter butterfly became one of his signature events because it rewarded both speed and endurance, qualities that later defined his international career. His long reach, powerful underwater work and unusually high training capacity made the stroke especially effective for him.

The record was not an overall senior world record. It was a national age-group mark for swimmers in his youth category, an important distinction that is often lost in simplified biographies. He kept the record for more than 15 years before another young American swimmer eventually surpassed it.

Phelps later won Olympic gold in the 100-meter butterfly at Athens 2004, Beijing 2008 and London 2012. His Beijing victory became especially famous because he defeated Serbia’s Milorad Čavić by one-hundredth of a second.