Transcript for 'Brutal' 7 Minutes a Day May Be Enough for Beach Body
You really get the perfect body just seven minutes. It's the work out that so many people are talking about after it was published in the New York Times magazine ABC's Claire Shipman David and -- she's joining us now from DC. Did tell us how it -- take our. Hey good morning where I took on this assignment because I too want to look as good as George. I also think it's seven minutes right how hard can it be let me tell you it hurts. And there's good science behind why it changes your -- Should this. And he doesn't look like this. The authors of a new study -- regular seven minute workouts may be enough to stay in shape. What makes this work -- standout is that the pure efficiency of the entire model as well as the fact that it can be done completely with body weight. He uses the basics of high intensity circuit training. Backed by solid science yeah. Studies show that when you -- close to your maximum capacity with resistance. For even a short time you can change your muscles in the same way a few hours of running Kenya. It's a brutal seven minutes all you need is a chair celebrity trainer Harley Pasternak -- -- proceeding with caution. Hillary I would say that there's a big danger factor if your sedentary or moderately sedentary and you -- -- trying do. Pretty intensity that suggested in -- gonna come only about. Halfway up but luckily I've spent the last few months working out with Erin sterling who happens to focus on this kind of intense circuit training in his Washington -- I asked him to get me through this it's very riskier than our normal speed. News twelve exercises with thirty seconds each at least fifteen -- with ten seconds breaks the breaks as -- as they are our heat. And the exercises are alternated between upper and lower body. How many more -- And knowingly -- made me do it twice to prove these -- intense workouts can make you feel immediately stronger even as you think you might dot still able to talk. Yes that's a thumbs up of. Because the right combination in the right sequence of muscles were were -- your actual performance. Improved while you look. For being so tired much better much were energized and did it. I ended up hurt and I don't think Lara would have made it through two times that I hadn't been worried about being humiliated on national television I felt good. Yet again it -- Thanks for doing that it's strong quarter for the heard a statement like that -- learn where to go -- -- did you -- -- Georgia votes. It was it was good sentiment work. I -- -- -- work -- machine and my house Olivia -- obviously never forget something I don't.
This transcript has been automatically generated and may not be 100% accurate.