Too funny! Dwayne "The Rock" Johnson and Jimmy Fallon starred in a totally hilarious fitness video skit during Tuesday, July 22's The Tonight Show.

Talking about Johnson's movie Hercules, Fallon asked the firm-biceped star how he got in shape for his roles.

"About a year ago I found this old VHS tape that had a bunch of clips of this fitness duo called The Fungo Brothers," Johnson said of his secret workout weapon.

A straight-faced Fallon nodded knowingly. "They were really ahead of their time," he agreed. "They were never quite successful but they were always so close to the next big thing."

Delving into NBC's archives, Fallon eventually dug up a clip of familiar-looking, floppy-haired duo Jack and Todd Fungo wearing fetching orange and blue wife beaters and squeezing a thigh cruncher between their legs.

"You know it's working when you feel the burn between your legs," declared Todd, aka Johnson, before sharing their workout motto, "You gotta hustle for the muscle!"

The super funny skit continues later with a 1950s version of the Fungo Brothers' hit show, showing Johnson and Fallon doing a fitness version of The Twist, throwing in some squat thrusts as they dance.

Click the link above to see the priceless video!