Ricki Lake: How I Lost 20 Pounds!

"They keep making my costumes smaller!" Dancing With the Stars standout Ricki Lake tells Us of her impressive slimdown on the ABC series. "I've lost at least 15 inches and I feel great!"

As well she should: Thanks to five weeks of marathon dance rehearsals with pro Derek Hough — and Freshology diet delivery meals — the 5-foot-4 mom of two has burned off more than 20 pounds.

"I'm working so hard," Lake, 43, tells the new issue of Us Weekly (out Friday). "It's a challenge to really push my body, but it's so fun!"

Having gone down three sizes since September, Lake — who's slated to host a syndicated talk show in 2012 — knows the value of her time in the rehearsal studio with Hough.

"I'm using muscles I wouldn't use in the gym or hiking, which is what I love to do," she explains. The best part? "Dancing doesn't feel like working out…even though I'm covered in sweat!"

For more on how Lake scored her sleek physique — including details on her workouts with fiance Christian Evans — check out her exclusive video chat with Us Weekly above!

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