"I was exercising so hard that I began to lose weight," the 17-year-old tells Men's Health in its December issue, out Nov. 17.
For most people, that'd be a good thing. But for Lautner, who wants to bulk up even further as the Twilight film series progresses, he had to go on a 3,200-calorie-a-day diet to put on mass.
"My character continues to grow, so I’d like to pack on at least a few more lean pounds," he says.
Whatever he's doing, it's working. Kristen Stewart had only good things to say about her costar's seeming makeover.
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