Our super time-efficient workout will make your heart (and heart rate) soar.


You know cross-training helps you get faster and stronger, but really—who has the time? We’re all busy! It’s hard enough to fit in our normal runs, much less add on extra sweat sessions.

Luckily for those whose schedules are packed, there is a form of exercise that’s a true unicorn. High-intensity interval training (HIIT) has been found to blast calories in no time (well, very little time!). In fact, a recent study from the U.K. found that participants achieved the same aerobic boost from 90 minutes per week of HIIT as they did from five hours of steady-state cardio. So what is this miracle workout? HIIT is a series of short but intense bursts of exercise followed by a recovery phase. Have 18 minutes? Give it a shot with this personal-trainer-approved HIIT workout!

Workout Instructions

Before you begin, warm up with a few minutes of easy jogging. Perform each exercise at the highest intensity you can maintain for 30 seconds (raising or lowering the difficulty based on your fitness level). Follow your 30 seconds of hard work with two minutes of recovery. During your recovery, walk or slowly jog in place to lower your heart rate and prepare yourself for the next exercise. Once you’ve completed all the movements, relax, you’re done. We said it was short—not easy!

Toe-Touch Jumping Jacks

Stand with your feet together and arms by your sides. Lower into a squat and reach down to touch your toes. Quickly jump up into a jack position, arms above your head and feet spread wide. Jump your feet back into a squat, reaching toward your toes. Repeat.

Beginner: Opt out of the toe-touch and do a normal jumping jack.

Advanced: Between each jack, spin around and face the opposite direction.

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Lateral Shuffles

Stand up straight with both feet together, then crouch down slightly and push your bum out behind you. Quickly push off your left foot and shuffle five steps to the right as fast as you can, keeping your core engaged. Shuffle to the left just as fast. Repeat.

Beginner: Slow down the shuffle.

Advanced: Lift your inside knee toward your chest before changing direction.

Running Knees

Stand with your feet together and arms straight overhead, reaching toward the sky. Start running in place as fast as you can. With each step, lift your knee as close to your chest as possible.

Beginner: Instead of running, perform high-knee walks.

Advanced: After every ten steps, add a tuck jump.

Plank Knee Pulls

Start in a plank position. Keeping your back and abdominals braced, bring one knee toward the opposite shoulder, exhaling as you pull it in, and then return your foot back to the ground. Repeat on the other side. Continue switching sides.

Beginner: Hold a plank position without moving your knees.

Advanced: Jump instead of step your feet, so that for a moment both feet are off the floor.

Plié Hops

Stand with your feet more than hip-width apart and toes turned out. Lower into a squat position with your arms in front of you. Jump up quickly, bringing your feet together and lifting your arms up over your head. Lower back into a squat position. Repeat.

Beginner: Do a regular plié squat with no jumps.

Advanced: Split your legs as you jump to create an x-shape mid-air.

Leap Frogs

Stand with your feet more than hip-width apart and squat down until your hands are on the floor in front of you (think: frog). Quickly jump up from the squat and leap into the air, immediately lowering into your frog stance. Repeat.

Beginner: Instead of jumping, just stand up and lower back down slowly.

Advanced: Jump to the left and right.

Burpees

Stand with your feet together and arms reaching toward the sky. Lower into a squat and plant your hands flat on the ground in front of you. Jump your feet into a plank position. Perform one pushup. Jump your feet back toward your hands. Jump up into the air and finish in the start position. Repeat.

Beginner: Lower into a plank position one leg at a time (no jumping), and skip the pushup.

Advanced: Jump into the air as high as you can when returning to the standing position.

*Ab-ded Bonus: This full-body routine doubles as an ab workout in disguise. The calorie-blasting power of HIIT uncovers a toned tummy (currently hidden under a cushiony layer), while the functional exercises strengthen your core.

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