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."