Running shoes are a touchy subject. Some people like minimal cushioning to promote good form, others prefer something more engineered. Adidas's new Energy Running push comes down on that side of the argument in an impressive way. Maybe even too impressive.

So "Energy Running" means Adidas has two new things to stick in its shoes. The first is Spring Blade, which is a new design that seems to snap back into place as you flex your foot. It's a simple, fairly elegant design.

The other is called Boost material. It's replacing a years-old industry standard of EVA foam, which is found in, according to Adidas, 90 to 95 percent of all running shoes. The big breakthrough is that it returns a ton of energy while remaining comfortable. Adidas says that until now, it hadn't been able to combine those two things, which is probably different from what it said before Boost, but that's the claim.

Adidas Energy Running: The Next Great Running Innovation, Or the Next Big Cheat

What "energy returning" means, basically, is that Boost is bouncy as hell. And that's going to, presumably, mean Bugs-Bunny-trampoline running shoes that are easier to run in. The comparison that Adidas set up is a metal ball bearing being dropped on concrete, EVA foam, and Boost. EVA was bouncier than concrete, but Boost was way bouncier than both.

The Boost material is rated to stay exactly as it is out of the box up to 500 kilometers, and Adidas claims it'll hold up better than other materials. But then, those other materials are rated to hold up and often underperform. It's a nice promise, though.

But the real question came from one of Adidas's guests: Is it legal? Because as fairly impressive as the tech sounds on stage, this "energy return" sounds a lot like the accelerating blade tech in Oscar Pistorius' running blades, or the over-streamlined nature of the swimming suits from a few years back that helped break multiple world records. Unlike a lot of other design changes over the years that have reduced speed and encouraged better human form, this is just straight up material saying it's going to enhance what you can do. Maybe that's just graphite rackets in tennis or space age drivers in golf, but it's still going to be a question if Boost is as good as Adidas says—which, of course, is a big if. Still, it's something to keep an eye on.

Adidas Energy Running: The Next Great Running Innovation, Or the Next Big Cheat

A lot of the developments in sports tech are snake oil. Like the compression gear fad, most of the new tech "breakthroughs" aren't much more than a new seasonal line to sell. After a few minutes with the Adidas Boost shoes, they're definitely comfortable and light. And yes, there's some bounce there—though it's hard to say how different it is from the Oh God I Can Run Anywhere feeling you get when you wear just about any pair of new running shoes.

So that's Energy Running. A lot of the promises will only be shaken out after extended use and long, long runs. Especially seeing how knees hold up when you're wearing springboards on your feet. Derrick Rose is an Adidas man, remember. But for now, it's promising, bordering on really cool, and if everything holds to form, possibly too good to be legal.