High-Intensity Interval Training FAQs Answered

There's a growing trend in the workout world called high-intensity interval training (HIIT), also referred to as speed interval training. Or, as some people think of it, running like you're being chased by a zombie, pausing to catch your breath, and then booking it again. Whew! And it's a concept that attracts firm believers.

More: High Intensity vs. Steady State Workouts

Michael Mosley, MD, a medical journalist in Britain, recently suggested that it's possible to improve fitness with just three minutes of exercise a week using HIIT. To prove it, he followed a HIIT routine that involved cycling on a stationary bike as hard as he could for 20 seconds three times, taking a few minutes to catch his breath in between the 20-second intervals. The result? After doing it three times a week for four weeks, his insulin sensitivity improved by 24 percent.

Certainly sounds impressive—who wouldn't like the idea of getting fit with less effort?—but could it work for you? We asked our experts to weigh in on the HIIT trend:

Does high-intensity interval training work?

"I'm a big fan of interval training, but the total bout of interval training needs to be within at least a 15- to 20-minute period to get maximum cardio and calorie benefits. You're not going to burn a lot of calories in a 3-minute workout; no matter how hard you train, you're only going to burn about 20 calories a minute." —Wayne L. Westcott, PhD, Prevention fitness advisor and fitness research director at Quincy College

More: How to Burn 100 Calories Without Trying

"I think it's highly effective and a great cross training workout. But in terms of overall health and cardiovascular endurance, there's nothing better than working out for 30 minutes three to four times a week. HIIT is a great thing to incorporate into your workout—the whole concept of burst and then recovery cycle for aerobic exercise is great—and it can help improve cardiovascular health faster according to recent studies." —Chris Freytag, Prevention contributing editor, trainer, and author of Two Week Total Body Turnaround

"I've used interval training in my step classes for years. Push hard for a minute or less and then keep going but at a much lower level of intensity, until it's time to crank it up again." —Kathy Kaehler, celebrity fitness trainer, author of Mom Energy

More: 3 Ways to Crank Up Your Metabolism

"I'm a big advocate for HIIT training. My mantra is that doing a little bit is better than nothing at all. If you're doing 10 minutes of a hard-core workout, you're going to burn more calories than doing a 20-minute workout at a slower pace." —Jennifer Cohen, founder and author of No Gym Required

More: Do-It-Yourself Home Gym

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Prevention

For 60 years, Prevention has delivered the kind of authoritative information, breaking news and energizing lifestyle advice that women can use today for a happier, healthier, stronger life tomorrow and beyond. With Prevention, she continuously discovers health, beauty, fitness and nutrition advice that makes her more inspired, more confident than ever before.
For 60 years, Prevention has delivered the kind of authoritative information, breaking news and energizing lifestyle advice that women can use today for a happier, healthier, stronger life tomorrow and beyond. With Prevention, she continuously discovers health, beauty, fitness and nutrition advice that makes her more inspired, more confident than ever before.

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