Transcript for Secret Behind Usain Bolt's Record-Breaking Speed
Now that's the good stuff. Kohl's. Card. I'm not a customer, but I'm calling about that Credit Scorecard. (To dog)give it. Sure! It's free for everyone. Oh! Well that's nice! And checking your score won't hurt your credit. Oh! (To dog)I'm so proud of you. Well thank you. Get your free Credit Scorecard at Discover.com. Even if you're not a customer. Leaf, we know that the best things in life are real. So we brew iced tea the way you brew it at home. For real, delicious, leaf-brewed iced tea. Pure and simple. Pure Leaf. For the Love of Leaves. Mr. Brady, we've been expecting you. Will you be needing anything else? Not a thing. Beautyrest black. Get your beautyrest. Back now with the olympics and inside look at the fastest man alive Jamaica's usain bolt. Blowing away the competition breaking down the science behind his speed. Who better to ask that than our man in Rio, T.J. Up there. A box on the roof. In the penthouse, hey, T.J. Hey, good morning once again, guys. Usain bolt would actually get a ticket if he ran through some neighborhoods in the U.S. For going over the speed limb, right? The guy is absolutely amazing. He's supposed to be too tall to be a sprinter but that works to his advantage. But it turns out he doesn't just have a physical but also a genetic advantage. Jamaican superstar usain bolt dominated the 200-meter semifinals overnight. And bolt is in front. Reporter: Proving to an effortless time of 19.78 seconds. He says, ah, no, I till got it. Reporter: On Sunday the world's fastest man crushed the 100-meter dash in 9.81 seconds making him the only person to win gold in the event three times. Here he is still invincible. Usain bolt. Reporter: So just how fast is bolt going? About 23 miles per hour. Keeping that same pace it would only take him about 2:40 to run one mile. That means he'd beat world class milers by more than five football fields but we may never know because bolt says he's never actually run a whole mile. One reason he's so fast, his height. At 6'5" bolt is above average for a sprinter so with his long legs it takes him only 40 or 41 strides over 100 meters when others need 43 or 44. He takes very long strides. And the speed of each stride is equal to what his shorter competitors do and that lets him chew up the track and make it look like they're standing still. Reporter: One other key to his success. In Jamaica people are active their whole lives and sporting culture starts young. Sprinters are not only the superstars in Jamaica they're the superduper stars and have been for a long while. Okay, robin, David, listen to this. They say, now, there's been some research about what's called an A.C.T. In 3 gene. It has to do with muscle explosiveness and say Jamaicans have a disproportionately amount that have in their country. More of them have this than anywhere in the word. That's part of the reason why we see so many good sprinters coming out of Jamaica. Interesting stuff, I don't know if it's true. The A.C.T.T.N 3 gene. Who is they? They, them. We just said it. The smart folks. Guess who is here today? You got king James. I got king James. I'll send your love. The champ is here. Live and the mvp is on a mission
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