Know how you can make a 10-minute workout effort seem interminably long? Focus on your abs—and incorporate high-intensity intervals. HIIT, famous for its fat-torching abilities, will enhance your muscle toning efforts with some quality calorie burning, even for hours after your session is done.

“This ab workout uses multi-plane movements to hit each area of the core in 10 minutes,” says Mark Beier, co-director of training at Shred415 in Chicago, who designed the routine. “The HIIT aspect of the high knees and football shuffles get the heart rate up while still utilizing the core muscles to perform those exercises.”

You’ll want to work hard but also aim for quality movement so you’re getting the most benefit out of this 10 minute challenge.

30 seconds high knees

30 seconds football shuffle/fast feet

1 minute straight-arm plank

30 seconds high knees

30 seconds football shuffle/fast feet

1 minute V-ups

30 seconds high knees

30 seconds football shuffle/fast feet

1 minute scissor kicks

30 seconds high knees

30 seconds football shuffle/fast feet

1 minute bicycle crunches

30 seconds high knees

30 seconds football shuffle/fast feet

1 minute opposite knee/opposite elbow mountain climbers

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