With all the skintight, cleavage-baring clothes that Kim Kardashian's been wearing lately, it's clear that working out is high on her list of priorities.

So it's only fitting that while in New York with hubby Kanye West and daughter North West, the reality star sweated it out, toning her famous assets at an 8:20 a.m. Butt & Legs class on Tuesday at Barry's Bootcamp in TriBeCa.

We're told that a makeup-free Kardashian and her pal, who she attended the class with, "received the VIP treatment" upon arrival, getting let into the studio before the other classgoers to handpick their treadmills.

"But they sweated it out just like everyone else during the class," a classgoer told us.