Ridiculously sculpted muscles don't just happen overnight. Dwayne The Rock Johnson had a pretty demanding exercise regimen to get in godlike shape for his latest film, Hercules . The wrestler-turned-actor stopped by The Tonight Show on Tuesday to let Jimmy Fallon in on his secret: a little-known workout duo known as The Fungo Brothers. The fictional Fungo Brothers even had their own version of the Shake Weight. Johnson took a moment to explain his now infamous #tbt Instagram.
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