Kate Bosworth in Bathing Suit Gets "Summer Ready"

Kate Bosworth is 39 years old and in the best shape of her life, thanks to an incredibly disciplined approach to diet and fitness (with some fun thrown in too!). "Here's how I get summer ready! (w/ a focus on fitness 💪🏻)" she captioned a recent Instagram post, which showed her doing Emsculpt. How does she stay so fit? Read on to see 7 ways the actress stays in shape and the photos that prove they work—and to get beach-ready yourself, don't miss these essential 30 Best-Ever Celebrity Bathing Suit Photos!

Bosworth swears by low-impact workout P.volve, which focuses on smaller ranges of motion. "I know that everyone thought the video I put up about P.volve was pretty funny," she says. "It's a provocative video, but it's actually such a wonderful piece of equipment. P.volve is really focused on those kind of low-impact, micro movements in order to target hard-to-reach areas."

Bosworth starts her days with a workout, and loves her trainer Stephanie Watson. "We met her on a TV show two years ago called the I-Land," Bosworth says. "She's also very focused on low-impact exercise and the mind-body connection. Her whole mission is low-impact fitness, and I learned everything I know about that from her."

Bosworth avoids overly-strenuous workouts these days, and focuses on the smaller victories. "I had a hard time with my exercise routine because I felt like it had to be an hour, and it had to be really rigorous and intense," she says. "Then, I realized you can go down and get on the treadmill for 20 minutes, and you've done something."df44d9eab23ea271ddde7545ae2c09ec

Bosworth loves to cook and eat, but behaves like an athlete when working. "When I'm working, I look at food as fuel. The hours can be long and irregular, and sometimes we work through the night," she says. "So I eat a lot of really good complex carbs, like sweet potato or chickpeas, protein and a lot of vegetables. During my time off, I make comfort food and don't worry so much about how the food makes me feel. But on set, it's almost like an athletic approach to performance. A healthy diet can bring a lot of stamina and endurance, and it's important if you want to perform to your best ability."

Bosworth is obsessed with cheeseburgers, and has two favorite spots to grab a bite. "I have two favorite cheeseburgers; one is from Burgers Never Say Die in Los Angeles, and the other from a place called Norm's News in Kalispell, Montana, which has one of the best cheeseburgers I've ever had."

Bosworth is a big fan of the Mediterranean diet, especially Israeli food. "I love the cuisine so much that to eat in the actual country would be a dream," she says. "I have a close group of Israeli friends, so it's what they cook for me. I love all the dips and spreads, and those fresh, crunchy, bright salads. I could just eat bowls of them, and they're great with marinated grilled meat. It's all healthy and super tasty."

Bosworth has been riding horses since she was five years old, which helped her get the lead role in Blue Crush. "I was a [horseback] jumper so, I likened surfing to horse riding only because I'd never surfed before and I had promised [producer] Brian Grazer and [director] John Stockwell that I would know how to surf by the time the cameras were rolling," she says. "It was a tall order. But the balance and the kind of [muscle] sensitivity, the horse riding and jumping and coordination that takes—I thought if I can do that, I should be able to surf. Surfing's harder. Maybe it's because I've been horse riding longer, but I do think that that kind of experience and also like a fearlessness when you're jumping really high fences on a live animal, you've got to have a certain brain to do that, or desire, you know… So I felt like if I can ride a horse, I can take on a wave."