So I’ve been trying this new thing I heard about called working out. I’ve found the perfect gym bag. Well, it’s actually a purse that can hold my sneakers and laptop at the same time. And now, I have my go-to sports bra.

Most of the sports bras I’ve tried in the past have landed on the same mediocre level. But this one actually impressed me before I even tried it on. Why? Because it actually tightens the more you move. So depending on your workout, the amount of support will increase as needed. Whether you’re going all out on the elliptical or Nextflix-ing and chilling, which is me 90 percent of the time I’m wearing a sports bra, it’ll adjust to the needs of your boobs.

Pretty impressive, right? Well, leave it to a big athletic brand like Reebok to come up with the clever idea. The brand aptly called the new design the PureMove Bra ($60; reebok.com). Not to get all technical on you, but it’s made with a Motion Sense Technology fabric, which is coated with Sheer Thickening Fluid. (That’s the secret sauce.) The Sheer Thickening Fluid is a flexible liquid when you aren’t moving much, and it condenses into a supportive gel the more you move. And believe it or not, the Sheer Thickening Fluid is so good, NASA uses it in its space suits, too.

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I, recently, put the PureMove Bra to the test during an intense TRX and Reformer workout at Flex Studios. And while I struggled through most of the moves (damn you, pushups), I didn’t have to worry about my boobs bouncing all over the place.