The Hercules actor stopped by NBC's Tonight Show Tuesday, where he joined the host for some silly exercise skits. Johnson set the segment up by saying he first got interested in fitness after watching the Fungo brothers' VHS tape. "They were really ahead of their time," Fallon joked. "All the fitness trends over the years—the Thighmaster, the Shake Weight—these guys did it first. They were never quite successful but they were always so close to the next big thing. It's amazing they never got credit for it."
Fallon then accessed the "vintage" clips via NBC's computer database.
Enter mop-topped fitness duo Jeff and Tad. "Do you wanna run faster do you want you your legs that will cause disasters and glutes that are harder than plaster?" Jeff (Fallon) asked. "You gotta get the thigh cruncher." Tad (Johnson) added, "You'll know it's working when you feel the burn between your legs."
They ended the demonstration with their catchphrase: "You've gotta hustle for the muscle!"
The next clip was from the '50s. Similar to what Chubby Chucker did with "The Twist," Fallon explained, the Fungo brothers "invented a dance that burned even more calories. It wasn't that big of a hit."
The Fungo brothers instructed viewers to "get on down and do the squat-thrust." Not quite as catchy.
The third and final clip showed the Fungo brothers using a tool similar to the Shake Weight called the Jack Weight. As its name might imply, the segment was filled with lewd innuendos about masturbation.
"If you wanna get packed and stacked, then you've gotta Jack it," Jeff said. "You've gotta Jack it in the morning. You can Jack it in the afternoon," Tad said. "Oh, god, and then you can even Jack it all night."
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