Well, not exactly a full time thing, Kitajima Kousuke who won gold medals for the Men's 100m and 200m Breaststroke at both the Athens 2004 and Beijing 2008 Olympics, will be voicing the original character "Pirate Kitajima" of the "Fishman pirates" in the new One Piece movie, One Piece Film Strong World!
He comments about the character he's voicing saying, "I don't know, he's got a way nicer body than me and looks cool." He even jokes saying, "I think he'd swim faster than me... I mean, he's a fish after all". Kitajima's favorite character is Zoro adding, "He's very much like me, in the part where he's able to 'crawl' his way back up even if he loses."
The movie is due out December 12thSource