‘Twilight’s’ Booboo Stewart flaunts his fit physique

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The dark-haired, muscular "Twilight" werewolf spotted running in L.A. Monday wasn't Taylor Lautner. Instead, it was 18-year-old Booboo Stewart showing off his fit physique! Stewart, who will reprise his role as Seth in "The Twilight Saga: Breaking Dawn — Part 2," which hits theaters November 16, made working out a priority long before his days on the silver screen. He won the Junior Martial Arts World Championship in 2002 and 2003 — beginning at the ripe old age of 8! "I don't really bring it up, people just find out. I just think it's cool," Stewart told ESPN. "They think it's crazy, it's so crazy to be a world champion so young. I don't know what I really think about it. It's just ... it's a really neat thing to do, so hopefully I can return to it one day."

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Stewart's young life also has included time making music. He was signed by Walt Disney Records at 12 as part of a group called T-Squad that toured with Miley Cyrus. Oh, and he's done stunts for movies, such as 2007's "Beowulf" with Angelina Jolie, along with other acting roles.

Despite his impressive resume, I couldn't help but wonder: What's the deal with Stewart's first name? As he explained to "Access Hollywood" in 2010 — you know, when he was so much younger — his real first name is Nils; Booboo was a nickname given to him by his mom when he was little because he used to suck two of his fingers, giving him "a boo boo face."

Well, it's definitely memorable!

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