Olympic Swimmer Ian Thorpe -- I'm Comfortable Saying I'm Gay

Five-time Olympic swimming gold medalist Ian Thorpe confirmed he's gay during an Australian sit-down interview Sunday ... after years of speculation over his sexuality.

Thorpe had denied he was gay for a long time, but told Network Ten he realized the truth about himself sometime in the past few weeks ... and started coming out to the people closest to him.

The Thorpedo -- who dominated the 2000 Summer Games in Sydney -- says he lied about his sexuality because he was too young at the time to know the truth.

Thorpe says he doesn't feel bad about lying either, explaining, "I’m comfortable saying I’m a gay man. And I don’t want young people to feel the same way that I did. You can grow up, you can be comfortable, and you can be gay."