Watch The Rock Vs. The "Thigh Cruncher"

If you’ve seen the trailer for the new movie Hercules (out this Friday), you know that its lead, Dwayne “The Rock” Johnson, is solid muscle. We might (read: definitely) follow the University-of-Miami-football-player-turned-pro-wrestler-turned-actor on social media, and have been privy to behind-the-scenes snapshots of his demi-god-like physique. Which is, in one word, impressive.

But, The Rock's muscle-building secret might surprise you. Last night, while appearing on The Tonight Show with host Jimmy Fallon, Johnson let it slip that the he used old VHS fitness tapes of "The Fungo Brothers" workouts to prep for his role. Cut to an SNL-worthy skit of Johnson and Fallon in full '80s-fitness-instructor glory — bunched-up socks, lustrous locks, and a "thigh cruncher.” “You gotta hustle for the muscle,” say the Fungo brothers.

The hilarious two-clip sketch delivered the Brothers' unique take on fitness, including a dance cardio routine that combines the twist with squat thrusts — as well as their version of the Shake Weight (complete with sexual innuendo). “This is not a workout; this is a revolution,” the brothers insist. While we never thought we'd witness Hercules crunch his thighs, we're certainly glad we did.