Check out this New York Times video article that reports on a new extreme sport described as a cross between parkour and trampolining. Go on. I’ll wait here while you watch.
Wasn’t that amazing? Doesn’t it make you want to dig out that crappy old trampoline/giant piece of sponge you messed around on as a kid, wedge it up against some wall, and jump! What I love about this video is that trampolining–an activity which has been universally decreed as uncool for anybody over the age of nine–when combined with parkour becomes an integral part of a high-energy, twisty camera angles, in-your-face EXTREME SPORT. It doesn’t even matter that one of the founding members of the sport is a computer-science graduate. Wall trampolining is set to take off in a big way. I bet it has another name by the time it gets to the X Games though . . .
Even more than trampolining’s imminent renaissance, though, what I loved most was how the introduction of a wall–a wall no less! I bet you’ve walked past loads of them today without the slightest notion of how cool they can be–exponentially complicated the essential act of bouncing. In a stroke the possibilities multiplied a hundred-fold. Hand-and-foot-plants. Lip tricks. Flip landings. All from the simple addition of a finite two-dimensional plane on one side of the trampoline. Simplicity leading to creativity.
Anyway, from a dynamical point of view, what was most interesting about this sport was that it worked at all. If you’ved watched even a few seconds of the video you might’ve found it uncanny that the bouncers leapt away from the wall, and yet after being ejected from the trampoline flew back the way they came. Were these extreme sportsmen and women breaking the law of conversation of momentum as well as their ankles? Surely they should’ve just bounced once on the trampoline, then landed on the floor on the other side? What was happening?
The answer lay in the design of trampoline. The bouncers point of contact with the trampoline was always slightly nearer the far-side than the wall-side. As the canvas stretched, the opposing force that slowed down the gymnast pointed back towards his or her direction of approach. They were making use of the trampoline’s inherent propensity to keep anyone bouncing normally on it in the middle–stray too close to the edge and you’d likely bounce back into the middle because of the differing tensions in the near and far springs. As the canvas snapped back, the bouncer was launched on a similar trajectory to the one they’d come in on! Potential to kinetic to elastic and all the way back again. No breaking of energy conversation either!
What would you combine to create a new extreme sport?
Image Credit: Wiki Commons