As water people, swimming should be part of our repertoires, right? But even if swimming isn’t part of your weekly health routine, you can definitely take something from athletes like Dara Torres. As a five-time Olympic swimmer, she knows a thing or two about core workouts. Hard to believe she’s 51. Yeah, you read that right. Maybe it’s because she does this core routine on the regular. Tech Insider caught up with the Los Angeles-native to get her take on an ab-crunch sequence that would do any surfer well (especially if you’re trying to keep your pop-up clean…um, dad?). Her exercises are done in 30-second intervals, making them easy to get done quickly, even if you’re traveling or, heaven forbid, working in an office.