Reap the benefits of hitting the weight room *and* high-intensity interval training with these killer workouts.
When You Only Have 20 Minutes
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When you combine HIIT with strength training, you have the potential to get insane workout results in a short period of time. Enter Lacey Stone, a badass LA-based trainer from Khloé Kardashian's E! series Revenge Body. She's all about hard-core workouts—and this 20-minute full-body workout (you'll work your chest, core, shoulders, back, legs, and arms) is no exception. We dare you to give this killer circuit a try.
Get the full workout and instructions: Celebrity Trainer Lacey Stone Shares Her 20-Minute Revenge Body Workout
When You Want to Make It a Total-Body Affair
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One of the best ways to stoke your metabolism (and, yes, burn fat) is to do compound movements (exercises that use a bunch of muscles, versus just a few). This dumbbell circuit from Nike master trainer Rebecca Kennedy is full of them—so you'll build strength while sending your heart rate sky-high. To make sure you're getting the benefits of HIIT, keep cranking out the reps and keep the rest to a minimum.
Get the full workout and instructions: The Best Exercises to Burn Fat
When You Want to Try Something ~New~
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Sure, lifting weights with correct form often means taking it a little slower. (Sometimes, that even means risking your endorphin rush.) However, that's not always the case. This 5x5 HIIT strength workout video from all-star trainer Jen Widerstrom (creator of the 40-Day Crush-Your-Goals Challenge) is proof. The genius thing here is that, during each strength interval, you perform the move slowly for the first 30 seconds, then crank the speed for the last 30 seconds, once your body is primed for the movement. The result? A 25-minute strength workout that actually gets you out of breath.
Get the full workout and instructions: This 25-Minute Cardio Workout Video Proves Strength Training Doesn't Have to Be Slow
When You Have Some Time to Kill
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If you love the variety of a circuit workout (FYI, here's the difference between circuit training and interval training) then this 45-minute strength HIIT circuit workout from F45 Training will be a total win. You'll cycle some cardio moves to get your blood pumping with, yes, some serious strength moves to score a full-body workout that rivals visiting the studio itself. Grab a friend (so you can call ownership over all this equipment at once), then hop to it with these workout instructions.
Get the full workout and instructions: The F45 Training HIIT Workout You Can Do In Any Gym
When You Want to Hit the Tread Too
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If you're an avid Barry's Bootcamp fan or love hitting the treadmill for some intervals, then this OrangeTheory-inspired HIIT strength workout video is for you. The key here is workout out at an intensity that keeps your heart rate at 84 to 91 percent of your max so that it truly counts as HIIT. (Start here: How to Find—and Train In—Your Personal Heart Rate Zones) You'll bounce from the treadmill to free weights to score all the muscle-building and metabolism-revving benefits of both cardio and strength workouts.
Get the full workout and instructions: The HIIT Workout That Maximizes Your Afterburn