His mouth may be wired shut, but a little thing like a broken jaw hasn't stopped Zac Efron from workin' on his muscles.

Efron, who broke his jaw last weekend by slipping on a puddle at his L.A. home, was spotted working out at a gym in Venice, California on Thursday, Nov. 14. Though the actor, 26, didn't move his mouth, he worked diligently on the weights and rowing machine.

"He looked great," a source told PEOPLE. "But it was all business. He was concentrating on hitting the weights hard."

While Efron might be putting on a brave face, his good friend and 'Hairspray' director, Adam Shankman revealed to the magazine that it hasn't been easy for the actor, who also completed a stint in rehab earlier this year.

"He has to eat through a straw in a syringe," Shankman said. "It's horrible."

Still, Efron has a lot to look forward to: beginning to promote his upcoming film 'That Awkward Moment,' (promo has been delayed due to his injury), and a possible reconciliation with his ex, Lily Collins, with whom he was recently spotted holding hands at Disneyland.

And if his dedication to the gym is any indication, it looks like everyone's favorite heartthrob will be all healed soon enough.