Official word came last week that Lautner, 16, would reprise the role of werewolf Jacob Black in the new movie.

There had been speculation that he might not be on board for New Moon, due to the character's radical physical transformation in the book series.

"I think it was a few weeks ago I had put on 20 pounds," Taylor told Access Hollywood.

"I started working out the day after I finished filming Twilight because I knew it was a necessity for the character... I guaranteed 10 more pounds, and I've already put on six."

The young actor then flexed his muscles for the camera, and lifted his shirt to show his washboard stomach.

Check it out below:

What do you think of Taylor's physical transformation? Does he get the part?