Could Roger Federer beat Rafael Nadal in arm wrestling?

Who would win an arm wrestling contest between Roger Federer and Rafa Nadal?

Don’t laugh. This was an actual question that Federer was asked Thursday in his Periscope Q&A with fans. He answered questions after filming a practice live on Periscope and Twitter in Dubai to promote the Hopman Cup, which he’ll play in January in Perth, Australia.

“Are you serious? No chance. My arms are so small,” Federer said with a chuckle when asked about Rafa.

And could Fed beat Novak Djokovic in an arm wrestling duel?

"I don’t think I’ve beaten anybody. Whoever I’ve arm wrestled I’ve lost against. If I’m good at anything, it’s probably rock, paper, scissors.”

For the record, Federer was a really good sport when answering questions about which musical instruments he can play (wooden flute as a kid, a little piano), whether he likes squash (loves the sport) and Star Wars (never has seen any of the movies. "Don't hate me.")