From Scrawny to Brawny: How Hollywood Shape-Shifts for Movie Roles

Jake Gyllenhaal in Southpaw.

At the end of November, pictures of Jake Gyllenhaal in his upcoming 2015 film Southpaw went viral because he was unrecognizable, thanks to a newly ripped boxer’s physique. It’s a time-honored tradition in Hollywood for actors and actresses to dramatically change their bodies to fully inhabit the characters they play, but it’s not easy and it usually requires a savvy team to make it happen. We tracked down a few of the pros responsible for sculpting some of Hollywood’s hottest bodies to find out exactly what it takes.

Think of any superhero movie that’s been released in the last 10 years and there’s a good chance Bobby Strom and his wife Alicia had a hand in transforming the leads into ass-kicking, six-pack-sporting machines. The duo trained Scarlett Johansson for Iron Man 2, Jessica Biel for Blade Trinity, andBlake Lively and Ryan Reynolds for Green Lantern, to name just a few. While it generally takes months of work and commitment, every situation is different. “With Scarlett, she dropped a few pounds of fat and added a few pounds of lean muscle. On somebody her size, it’s very obvious,” Strom explains. “Ryan Reynolds is six-three and very long limbed, so you need to add a lot to see a visual change.”

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Renee Zellweger put on 20 pounds to play Bridget Jones inBridget Jones’s Diary.

Basically, a thirty-minute jaunt on the elliptical a few times a week isn’t going to cut it if you’re trying to bulk up or get lean. Deadline reports that Gyllenhaal trained twice a day every day with real boxing coaches for several months. Strom has his clients work out five to six days a week doing various combinations of resistance training with equipment and their own body weight, cardio drills like sprinting and rowing, and core and balance training, without any breaks in between exercises. (Core training is especially important if an actor is doing his or her own stunts—it might look sexy on camera, but it also helps prevent injuries.)

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For 2014’s Gone Girl, Rosamund Pike had to gain and lose weight four times while shooting according to her trainer, Holly Lawson, who’s also a professional boxer. Lawson spent every day for about six months with Pike before and during shooting. “We had two and a half weeks to put weight on her, she went to film in Missouri, and then she came back and we had 10 days to take all that weight off her,” Lawson says. To accomplish this, Lawson had Pike put on almost eight pounds of muscle with heavy lifting and a very specific eating plan (more on that in a minute).

Hillary Swank showed off major muscles in Million Dollar Baby.

Lawson had the actress pack on an additional seven to eight pounds of fat over the muscle, which apparently gives the effect of heft—since the camera packs on weight anyway. Strom uses Sylvester Stallone’s Rocky character as another example. Stallone didn’t actually weigh what a heavyweight boxer is supposed to weigh when he filmed the movies, but “when you’re defined, you look bigger and heavier. It can visually add 20 pounds, and on camera it’s even more,” Strom explains.

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When Pike needed to look really lean again in a short period of time, Lawson put her on a high intensity cardio program twice a day to get rid of the excess flab. The result? “When you strip the fat off, you might be heavier than you’ve ever been, but you’re going to look better,” Lawson explains. “Rosamund had never had a six-pack in her life and she did in the movie.” If you think that sounds bad, Pike had to repeat the whole process again for re-shoots.

While exercise and training are key to sculpting the body a director wants, you can’t do it without the right type of nutrition—and that’s truly a science. Lawson had Pike eat “healthy fat and good proteins like avocado and salmon to feed muscle,” then had her eat fatty and high sodium foods to add bloat—which is fairly easy to get rid of—as well as fat when she needed to bulk up. To slim down, Pike ate a sodium- and fat-restricted diet and cut out carbs (except for cruciferous vegetables) and dairy.

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Food provides the body’s building blocks, quite literally. “I could train you to lift the heaviest weight in here, but you’re not going to get big from lifting heavy weights,” Strom says. “You’re going to get big from lifting a fork in your kitchen.” And by big, he means ripped or rippled, depending on what you eat.

According to Strom, Hillary Swank ate 5,000 to 6,000 calories, sometimes even waking up in the middle of the night to chow down, in order to put on muscle weight forMillion Dollar Baby. She did it by eating red meat, eggs, and protein shakes combined with a rigorous weight-training program. Renee Zellweger’s doughnut-fueled weight gain journey to play the flabby Bridget Jones is now legendary, and Strom helped Benecio Del Toro similarly gain 50 pounds of fat for 1998’s Fear and Loathing in Las Vegas. While he tried to have the actor focus on eating healthier fats like almond butter, gaining that much weight is never healthy. Both Del Toro and Zellweger have said they’d hesitate before ever doing it again.

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While it can take months to look like a superhero, it only takes a few weeks of downtime in Cabo and a couple of margaritas to lose it all. The trainers both stress that we, the movie going public, shouldn’t feel bad if we never have the physique to don a latex cat suit because few people can reach that kind of perfection—and no one can maintain it forever. Actors are motivated by multi-million dollar paychecks, after all. “If you’re not getting paid money to drastically alter your body, that is not something you really need to subscribe to,” Lawson advises. Both trainers also say that gaining and losing weight quickly can be unhealthy, so you should never try to do anything this dramatic, at least, not until you’re tapped to star in a Wonder Woman flick.

Instead, use this knowledge as motivation to get moving. Strom tells all the actresses he works with to maintain a two to three day per week exercise schedule after shooting, and it’s good advice for non-Hollywood types, too. “That consistency will always put you in a place where you can do anything you want,” he says. Lawson recommends setting reasonable and attainable goals that have nothing to do with a number on the scale. “You need to set a performance goal or an aesthetic one if it’s reasonable,” she says. “It [shouldn’t be], ‘I want to be a size zero.’” She suggests setting a goal to run a 10k or to have more defined shoulders, or something similarly narrow.

Tweaking your diet a bit can also reap fairly quick rewards, which will help keep you motivated. Lose the salt and you could lose some paunch. “If you’re eating a crappy diet, the easiest thing to do is to shed sodium and some water weight, and you’ll immediately look and feel better,” Lawson says. She also recommends drinking a gallon of water per day. At meals, fill most of your plate with fruits and vegetables, and the rest with lean protein, some whole grains, and good fats like avocado.

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Most importantly, keep your expectations reasonable. “Let’s be very real. Rosamund is a movie star and is paid to be onscreen and she’s beautiful and photogenic and all those things, but she struggles just as hard as the rest of us,” Lawson says. “You should be doing things to make yourself the best version of you possible.”