ADMIRE THOSE RIDICULOUSLY ripped guys from The Expendables? Here’s a secret that’ll come as both a relief and a letdown: Physiques like those of Stallone and crew have the life expectancy of a mayfly—a day or two after the shoot.

We’re not saying it’s CGI or Photoshop that’s responsible for creating these onscreen bodies. Rather, it’s a secret, weeklong get-shredded strategy that separates people who make their living with their bodies from guys like us who just want to eat popcorn and watch them dodge bullets. The movie stars, the underwear models, the pro bodybuilders—they don’t look like that all the time. They can’t. But when it’s go time, they’re ready with Hollywood’s biggest get-shredded secret.