In high jump, your centre of mass goes under the bar

[Applause] I am about 1.75 m tall, but some of the world's best high jumpers can clear more than half a meter above. [Applause] [Music]

That this is Josh Lodge, an Australian high jumper. What's your personal best high jump? 2 minutes 22? That's pretty high. The record is uh s myor from Cuba; it's about this high 8T and a half an inch, 245. Uh, same height as a full men's volleyball net.

Can you tell me about what it's like to be a high jumper? It's just really fun. Like, everyone who sees it, I know, always wants to do it, right? Yeah. [Music] Exactly. So, can you teach me to jump as high as you?

Uh, I don't know. He knows that he can't. Tell me about the technique that all the modern high jumpers use. So they do the Fosbury Flop. So that's with the J curved run-up. Generally, you have a straightish sort of part, and then the last part of the run-up is curved. It's half straight, half curved.

Yeah, so that you can have more speed, and it puts you in the right position to then get the rotation and go over on your back. And what foot do you take off on? Uh, you take off on your left foot.

Yeah, yeah, that's right. So if you can only really think about one thing: drive up that leg! I tell people to drive up that [Music] leg. So what did I do wrong there? Well, how much time do we have? You started on the wrong foot. Come on, you can get this.

So before The Fosbury Flop, the main technique that people used was the straddle. Yeah, the straddle, or I think it was also known as the western roll. With that technique, athletes came on a much sharper angle to the bar in a straight line, and they took off from their leg closest to the bar.

And um, did they go up frontwards or also back? They went over the bar on their front. They still required some sort of mats for the straddle. But I'll show you a scissor; that was another one that was from the days when you had to land on your feet—the days of sawdust.

So I think that was more like before the 50s—pretty much the same as a takeoff to Fosbury Flop, and then you just land on your feet. Yeah, you land on your [Music] feet. That's a really old one, and it's what they did when they didn't have any mats.

So really adding the mat really changed the way people jumped. Yeah, yeah, and obviously without having to worry about landing safely, they could jump higher.

Regarding the physics of it, why is The Fosbury Flop the superior technique? Well, I've heard that it allows your center of mass to actually pass underneath the bar. Your entire body clears the bar, but not all at once.

So you're keeping, like, your legs and your arms sort of underneath the bar. If you average where your center of mass is, it's under the bar, whereas, like, the other techniques, they seem to, you know, you have to have your whole center of mass clearing the bar.

So technically, it's harder. Like, you're getting your mass up high in order to clear the bar. Yeah, that would make sense because with the straddle technique, when you go over, you've got half your body going over the bar all at once.

Yeah, whereas in the Flop, my coach used to talk about it like a hose. So the water coming out of a hose—you only need to get each bit above the bar at the right time, as opposed to all of it at [Music] [Applause] once. [Music] [Music] [Applause] [Music]