Celebrity Shape-Up

ROLE Counter-intelligence agent Shana "Scarlett" O'Hara.
WORKOUT PLAN Nichols worked with her longtime trainer Valerie Waters to get into fighting shape for GI Joe. For the four months leading up to filming, Waters replaced Nichols's regular routine with three weekly full-body circuit workouts she calls, "Action Hero Babe." The circuits are each made up of 4-5 exercises that work arm, core, leg and back muscles. "It was very specifically designed to add a little more muscle than usual," says Waters. "We wanted her to look believable pulling off the action, but still stay super sexy."