"I think ping pong is the most fun way to stay in shape," says the actress. "You really work up a sweat and it's fun. It's good for your mind as well as your body."
Sarandon chatted with PEOPLE at Manhattan's Madison Square Park on Sunday, where tables from SPiN – the Manhattan ping pong club in which she's an investor – were set up for people watching the U.S. Open.
The Oscar winner, who turns 64 next month and stars in the upcoming Oliver Stone film Wall Street: Money Never Sleeps, even touts ping pong as a superior exercise to others she's tried.
"Unlike the treadmill, which kills brain cells, this actually invigorates you," said Sarandon at the event, presented by Zync from American Express. "In the past I've had a trainer, and I like yoga, but now my resolution is to play [ping pong] like, every day."
But first she has to get healthy. After injuring her foot on a mission to Haiti, the newly single star is hoping to step up her table tennis routine.
"I've only been able to get sneakers on for the last week," she says. "So now I'd like to get a schedule to train regularly."