By Kim Peiffer
May 27, 2016 @ 4:15 pm

Want the ultimate six-pack? Then look no further than the Tone It Up Girls. After all, we don’t know anyone who loves a bikini more than TIU co-founders Karena and Katrina. But what’s the best move for getting washboard abs? We invited the girls into our New York City studio to show us an exclusive InStyle ab workout that can be done right in your own living room.

To perform the move, come down into a plank position so that your shoulders are right over your wrists. Holding your abs tight, draw your belly button into your spine and hold. Next, bring your right knee to your right elbow, squeezing those obliques. To add a booty move to the mix, kick the foot up to work the glutes. Alternate sides, performing 10-20 reps on each side, three times.

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This move targets the oblique muscles, which give you those beautiful lines on your waistline. Now you’re ready for bikini season!