The trending fitness mantra “strong is the new skinny” has us hitting the weight room a little harder these days, and it sounds like Kristin Cavallari, former star of The Hills and host of The Fabulist, is lifting right along with us.

The 28-year-old actress and shoe designer has been working hard in the gym after giving birth to her second child, but not because she wants to slim down.

“I don’t know why or how, but after I had children, my body literally changed. And now for me, it’s about trying to keep muscle on and gain muscle, so that, yeah, I don’t look too thin,”  she recently told E! News. “It's very easy, especially because I have no curves, that I can look really skinny, and I don’t like that look.”

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"So, yes, I'm drinking protein shakes, I'm trying to put on muscle, and I'm lifting very heavy weight right now," she said. (She says her husband, Chicago Bears quarterback Jay Cutler, is great with workout tips and actually introduced her to her trainer.)

Building muscle can do wonders for the body, and we aren’t just talking about sculpting beautiful biceps. There are major health benefits of strength training including a boosted metabolism, better memory, stronger bones, and more.

So keep doing those power moves, Kristin—they're great for you in more ways than one.

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