Improvisational Sports

I found my mouse pointing me to this video on the Internet.

Here's the only explanation of I could find:

"Milwaukee kids pass a summer's day in what one of them calls 'The Ghetto Olympics' -- doing back flips and other gymnastics on mattresses stacked on the ground. They're joined by a man who was driving by and stopped to relive a bit of his childhood."

And I find myself watching and watching and thinking: "improvised sport," and "Hmmmm," and "isn't that what Junkyard Sports are/is? Improvisational sports?" and "Ghetto Olympics?!" and isn't it even more cool that we have yet another name for it? Improvisational Sports? Sports that you make up as you go along, so to speak, even though there's a, also to speak, 'script' with roles and rules and stuff."