How long should you do HIIT training for?
"I think this type of workout is best three times a week if you do it properly. You need every other day to recover." —Kathy Kaehler
"Try to do HIIT twice a week. I use it more for conditioning and to shock my body into something I'm not used to doing. It's great to do it as part of your workout, but not your only form of exercise because it doesn't train you for overall wellness." —Jennifer Cohen
More: How to Add High Intensity Interval Training to Your Workout
"I don't know if there's any exact perfect time. Continuous aerobic training is usually 20 minutes or more. I like the Tabata method of training that involves 20 seconds of high intensity and 10 seconds of recovery. Do eight cycles of 20 seconds hard, 10 seconds rest, in a row. That appeals to me because I think 'I can do anything for 20 seconds.'" —Chris Freytag
More: What Is Tabata Training?
Is HIIT safe for beginners?
"There is much more deficit than benefit to these types of programs for beginners. If they did do it, I certainly would want them to take a long warm up and a long cool down before doing something that intense." —Wayne L. Westcott
More: 4 Warm-Ups for a Better Workout
"I wouldn't recommend this type of training to a beginner—it's a perfect way to turn them off. This is more effective and welcoming for someone who is already involved in a program." —Kathy Kaehler
"A beginner is more likely to get injured because their technique gets compromised if they don't know what they're doing." —Jennifer Cohen
"I think it can be adapted for anyone. It's great for your basic fitness enthusiasts and recreational exercisers. Try some high-intensity training to burn more calories in less time and get the heart health benefits. For your average fitness enthusiast, I suggest working to the point where you're breathing so hard you can't talk, and then pull it back to where you can still breathe." —Chris Freytag
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