On the left is Sean Connery in the 1974 movie Zardoz. On the right is the Hugh Jackman in the 2013 movie The Wolverine. Physically, there's a lot of difference. In years past, actors could do some casual exercise on their own and then show up on the set.
But those times are over. Now American movie studios have a concrete conception of the ideal male body. Specifically, it's what Brad Pitt looked like in the 1999 movie Fight Club: quite a bit of muscle, but it's all lean. Every muscle is defined and vein popped. It's important to be very muscular, but it's equally important to have very low body fat. And when it's time for an actor to appear nude or shirtless, that actor has to use every bodybuilding trick available to enhance his muscular definition.
There's a lot of money to be made in an action movie, so studios invest heavily in top notch trainers who rigorously discipline actors. Logan Hill wrote a lengthy article in Men's Journal wrote about this industry:
To get that hungry look, trainers stress calorie-conscious diets and exercises that pump up fat-burning metabolism. No actor can gain 10 pounds of muscle in a six-week period, but he can lean down to reveal the muscle underneath. Trainers talk about the "lean out" – the final, preshoot crash period when actors drop their BMI (body-mass index) to its bare minimum and unveil muscle definition.
But maintaining extremely low body fat for the duration of a multimonth shoot is nearly impossible and often dangerous: The stress can make an actor ill, damage internal organs, and make him susceptible to other injuries. Matt Damon, who dropped 40 pounds without supervision for 1996's Courage Under Fire, got so sick that he was beset by dizzy spells on set, impairing his adrenal gland and nearly doing serious damage to his heart. Even in the best-case scenario, calorie deprivation can exhaust an actor, making him light-headed, distracted, and fatigued.
Since 5 percent body fat is nobody's natural condition, fitness plans are geared to peak on the days of the sex scenes or shirtless moments. To prep for these days, trainers will dehydrate a client like a boxing manager sweats a fighter down to weight. They often switch him to a low- or no-sodium diet three or four days in advance, fade out the carbohydrates, brew up diuretics like herbal teas, and then push cardio to sweat out water – all to accentuate muscle definition for the key scenes.
The last-minute pump comes right before the cameras roll. Philip Winchester, the hero of Cinemax's action series Strike Back, recalls seeing the technique for the first time on the set of Snatch: "Hundreds of extras were standing around," he recalls, "and Brad Pitt would drop down and do 25 push-ups before each scene. I thought, 'Why is he showing off?' " Then Winchester figured it out. "I realized he was just jacking himself up: getting blood flowing to the muscles. I'd always wondered, 'How do actors look so jacked all the time?' Well, they don't. Now we ask: Is it a push-up scene? When I shot that Strike Back poster, I was doing push-ups like a madman, saying, 'Take the picture now! Take it now!' "
Part of the training includes taking testosterone supplements and human growth hormone. But not steroids:
"In Hollywood, the drug of choice is the drug that makes you look good," says Strike Back's Winchester. "It's like the drug scene at a boarding school – it's all available." When actors ask about steroids, trainer Steve Zim tells them about the hair loss and zits, and "that usually ends the conversation in one second." Steroids also produce rounder, water-retaining muscles instead of the lean, mean bodies currently in vogue. Testosterone and HGH are far more common, particularly for older actors, since lower levels of testosterone can make it impossible to retain muscle mass. "Over 40? I encourage getting tested," says trainer Bobby Strom, "but there are some trainers who just go right to the testosterone, like they're putting you on a multivitamin."
Zim has seen the benefits of hormone therapy firsthand. "These people who look younger and fitter – a lot of them are using growth hormone and testosterone; the size comes from the testosterone, the virility and the youth come from the growth hormone."
-via Marginal Revolution