Christian Bale lost about 70lbs in 3 months for the Machinist
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Charlie Sheen built muscles for Hot Shots! Part Deux
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Russell Crowe gained 63lbs for Body of Lies
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Jake Gyllenhaal gained 25lbs of muscle for Jarhead
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Ben Stiller build some muscles for Tropic Thunder
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George Clooney gained 30lbs of fat for Syriana
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Linda Hamilton toned up really well for Terminator 2
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Hilary Swank put on a lot of muscle of Million Dollar Baby
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Mr. Stallone put on about 40 lbs of fat for Copland
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Tom Hanks lost about 50lbs for his movie Cast Away
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Renee Zellweger gained a lot of weight for both Bridget Jones movies
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Demi Moore gained muscle for G.I.Jane doing one arm pushups
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Jessica Biel gained some really defined muscles for Blade Trinity
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Matt Damon lost 40lbs for Courage Under Fire
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Gerard Butler gained muscle for 300
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Ed Norton (yeah the skinny dude) gained muscles for America History X
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Charlize Theron became ugly and gained a lot of weight for Monster
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Eric Bana Ballooned up for his role in Chopper
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Ryan Renolds packed on some serious muscle for the Blade movies
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