Arizona Congresswoman Kyrsten Sinema is heading back to Washington after completing the grueling Ironman Arizona triathlon in Tempe.

Sinema completed the event Sunday in 15 hours, 12 minutes, 34 seconds to become what organizers of the Ironman international competition say is the first sitting member of Congress to complete the event.

The first-term Democratic lawmaker representing Arizona’s 9th Congressional District completed a 2.4-mile swim, a 112-mile cycling ride and a 26.2-mile run.

She had hoped to complete the race in under 16 hours.

Sinema didn’t even know how to swim before beginning to train for the event about a year ago. She hired Olympic gold medalist Misty Hyman as her coach.

Sinema spokesman Justin Unga said she was on a plane headed back to Washington Monday morning.