Seth Rogen's Crimefighter Weight-Loss Plan!

The star of Zack & Miri Make a Porno talks about plans to drop pounds before making The Green Hornet

Seth Rogen is now too skinny to play that chubby funnyguy Seth Rogen in a movie. "I'm sellin' out, guys," a slimmer Seth tells E! News at this week's Zack and Miri Make a Porno press day.

"It's for The Green Hornet," he says of his upcoming flick. "The only reason. There's no other reason. I think it serves the movie."

To play the legendary costumed crimefighter, there's no quickie detox or reality-show competition for Seth. "It's the lamest answer ever," he confesses. "I eat well and I exercise."

Easy, then. No burgers, plus a brutal trainer. "I go there real early in the morning," Seth says. "He tells me what to do, and I go home and go to sleep, and it's like it never even happened."

So how many pounds? You can tell us, man. "I don't weigh myself."

But as soon as Green Hornet wraps, expect the big old Seth we know and love. "I think it will take three hours," he says.

The Green Hornet begins shooting in May.