UNIVERSAL CITY, Calif. (AP) — Aziz Ansari says he's spent his whole career preparing to host the MTV Movie Awards.

The 27-year-old actor and comedian, a star of NBC's "Parks and Recreation," has been making short films and doing standup since college. He'll get to do both — along with a big musical number "in the style of my R&B hero, R. Kelly" — at Sunday's show, to be broadcast live from the Gibson Amphitheatre.

"I've trained myself for this stuff without realizing it," he says, relaxing briefly in the green room after a rehearsal Saturday.

Ansari got his start on MTV, doing sketch comedy and short films for the show he helped create, "Human Giant," which ran on the network in 2007 and 2008.

Now, the slim, baby-faced comic is everywhere. A star of the new movie "Get Him to the Greek," Ansari just released an hourlong standup special, has three films in development with Judd Apatow and is launching a standup tour this summer.

"On top of all that, I manage the Arby's on La Brea and Sunset, so it's really tough," he quips.

Ansari confesses that he's "kind of a workaholic."

"I don't even remember what I do when I'm not working because I've been working so much," he says.

Though his life's work readied him for the MTV gig, Ansari prepared further, immersing himself in the year's nominated films, including "The Proposal," ''Twilight: New Moon" and "Avatar."

He called upon "The Hangover" star Zach Galifianakis and his "Human Giant" co-stars to appear in short films for the show. Then he strapped on his dancing shoes to create his laugh-packed musical number.

He practiced the routine Saturday, drawing applause from an audience of stand-ins and show workers.

Other things to expect at Sunday's show? Scores of celebrities, a dazzling set that practically fills the theater with movie screens and a slam at British Petroleum that brought the house down during rehearsals.

The MTV Movie Awards are a fan-centered celebration of the year's most popular films, which are honored in categories including best kiss and best fight, among others. Fans chose the nominees and winners through online votes.

Tom Cruise, Cameron Diaz, Adam Sandler, Betty White, Will Ferrell, Zac Efron and dozens of other celebrities are set to appear on the show, where Sandra Bullock is to receive the Generation Award.

Though this is Ansari's first time hosting an awards show, nerves aren't a problem.

"I work really hard to prepare so that I'm so confident that I'm not nervous," he says. "The short films, I have them and I edited them and I know they're good. Then the monologue, I just did standup every night for a while and really honed it and got it good.

"So if it doesn't work," he continues, "the audience is just wrong."

Look for complete coverage of the MTV Movie Awards Sunday beginning at 4 PM PT/7 PM ET on HitFix.

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