Transcript for The 7-Minute Workout Sweeps the Country
sweeping the country? Finally an exercise routine that takes the same amount of time it takes to heat up a frozen din center a dream come true? Gio benitez puts it the test and has the answers. Reporter: It's the latest fitness craze -- the "new york times" said, 7 times and you're done! The 7 minute workout spawned a mini industry, dozens of smartphone apps, countless youtube training clips and now even a music video. ♪ Reporter: Some people swear by it, like supercharged executive heather holland. Basic philosophy, increase the workout intensity, decrease the time. I'm winded and sweeting. So you can see that it works. Reporter: We asked exercise physiologist polly de mille to put heather's 7 minute to the test. The machine will tell us how much oxygen your body is using, how much carbon dioxide it's producing. Reporter: Heather's heart rate quickly escalated from 96 to 163 beats per minute. In seven minutes, she burned 52 calories. The scientist says that's good, but -- there probably isn't enough research to say this is all you need to do. Nice and simple. Reporter: So we tracked down chris jordan, who developed the workout, published by the american college of sports medicine. Did he really me to say that 7 minutes is all it takes? Although this has been pushed around as a seven minute workout, we recommend doing it not once, but three times for a good hard vigorous workout. Reporter: What? You heard him. Three times, three times. Reporter: That makes it a 21-minute workout. He explained that while a shorted more intense workout elevates the heart rate and targets all the major muscle groups, unless you do it three times in a row, you won't get complete workout. So at seven minutes, it might not be the best workout, but i can tell you, it still packs a punch. How you doing, okay? Jr. Gio benitez, abc news, new york.
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