This Simple Exercise Helped Kim Kardashian Get in Her Best Shape Ever

Kim Kardashian West played no games getting back to her pre-baby weight after welcoming her son Saint, and once she did ... she never looked back.

Just one look at the Keeping Up with the Kardashians star in her vintage Dior bikini on her latest vacay (sister Kourtney Kardashian's birthday extravaganza) will show you the mom of two is still working hard to keep her physique in check.

And there's one simple exercise she's been doing that has helped her get into the best shape of her life: jump roping.

The reality mogul, who works out often with Don "DB" Donamatrix and Gunnar Peterson, shows off some of her fitness secrets every now and then on Snapchat. On a recent occasion, Kim could be seen jump roping on a massive basketball court as Khloé Kardashian worked out nearby—and gave her major props. "How'd you do that?!" Khloé exclaimed. "You're so good Kimberly. That's crazy. Kim is like a legit jump roper."

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Of course, jump roping isn't the only thing that keeps Kim ready for bikini season. Earlier this week, she posted a snap of herself doing lunges all the way up a steep hill and running too. "Alright you guys, I'm exhausted ... but I did it," she said breathlessly in the clip. "I lunged up the whole way."

She also sprints, and works out early in the morning, as indicated by one workout snap labeled "6:11 a.m."

Since diet is just as important as fitness, Kim makes sure to eat healthy as much as possible too, and shared a photo of her breakfast this week—avocado, eggs, cucumbers and tomato slices—which she captioned "Gross".

Gross or not, all of her hard work is paying off. Keep the fitspiration coming, Kim!