on right now to, well, imagine this, getting thinner and healthier with just one minute of exercise, people, but you do have to do it three times a week, that though is a prols of the book everybody... See More
on right now to, well, imagine this, getting thinner and healthier with just one minute of exercise, people, but you do have to do it three times a week, that though is a prols of the book everybody is talking about called "Fast exercise," ABC's juju Chang found out you don't even have to change out of your business clothes to get it done. Reporter: First it was seven minutes then four minutes and now a 20-second workout. Oh, my god. I can't -- Reporter: In 20 seconds you can change a profile pick, give a hug, maybe sing happy birthday but what about this? Go. Okay. Reporter: Dr. Michael mosley said three 0-second burst, a minute three typiepypes times a week will make you not only skinnier but healthier. We met at the reebok sports club in New York. What's the key to high intensity. It seems to be much more effective not only for losing weight but also for improving your -- Reporter: It's the stress and intensity, not duration, we're talking about weight loss, reduced cancer risk and something close to Michael, diabetes. Two years ago I discovereds of a diabetes, that got me into fast exercise and now I'm 20 pounds lighter and my blood sugars are completely Normal. Reporter: As a Guinea pig he said he doesn't need a fancy gym or even gym clothes. Why am I getting nervous. I'll give you a head start. Ready, steady, go. Reporter: You can do this one right in your stairwell. Let's do -- Reporter: That's it, that was intense. That's humiliates. You were so much faster than me. Daniel teaches high intensity workouts at reebok. A lot of people it's like I've got kid, I've got my kids and have to get grocery, it's nice to get in, get out, hit it hard and I'm done. I don't think ten minutes three types a day will be enough. Reporter: Mosle yechlt says scientists all over the world are finding amazing health benefits doing better fitness in less time. Luckily for me it's almost time for the recovery period. Are we done yet? Yes. Reporter: For "Good morning America," juju Chang, ABC news, New York. Okay, that was intense. And you can get more 20, 30 and 60-minute workouts from his new book at goodmorningamerica.com on Yahoo! What do you think? I think it's worth a trial. One minute is better than no exercise. Feel like I really want it to be true. Yeah. We'll take a shot. In the stairwell. Meet you there.
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