Zac Efron knows the value of a good workout buddy. We're fairly sure that his YouTube series "Gym Time" is just a clever way to work out with as many fun people as possible; see his videos with Alexandra Daddario, Nina Dobrev, and a group of Victoria's Secret models for our supporting evidence.
His latest workout with YouTube star Liza Koshy might go down as the most entertaining one yet. There are subtle High School Musical references, so many high-fives, and a deep Q & A session while balancing on a stability ball (as one does). The workout itself? It's no joke. Zac and Liza go through some challenging plank and glute bridge variations, forward and backward lunges, and battle rope sequences before ending with a stability ball plank. Check out the full workout above to get all their moves and a healthy dose of gym buddy FOMO.