I love scrappy upstarts. I love that my Neato Botvac Connected robotic vacuum cleans the clock of my sister’s Roomba. I love that Dollar Shave Club carved out a billion dollar slice of Gillette’s market with a hundred or so employees. I even love that DJI crushed GoPro in the aerial camera market.

That said, when my Nike Hyperdunk basketball shoes fell apart, I couldn’t help but support Athletic Propulsion Labs (APL), a Southern California startup selling shoes that promise to make you jump higher. I was less interested in the concept of jumping higher (my vertical must have dropped 6″ in the last five years) than by the idea of a scrappy startup challenging the Nikes and Under Armors of the world.

I placed my order for a pair of $175 Concept 3 shoes about a year ago and have played once a week or so in the shoes until they fell apart last week. Overall, they were fine shoes and felt a little springy, but weighted probably 100 g more than a pair of Hyperdunks, to which I switched back. Playing in them was kind of fun–almost like running around in moon shoes. I wouldn’t say that they added to my vertical, but they definitely had some kind of spring buried inside.

However, after searching all over the internet, I couldn’t find a single post explaining what the hell was in the APL Concept 3 shoes, so I decided to dissect mine after they fell apart and show the autopsy to the world right here.

I sliced the shoe in half perpendicular to the axis of the foot just below the Load ‘n’ Launch pad. Looking toward the heel, the shoe is nothing out of the ordinary–a rubber sole, capping a foam midsole, topped by a foam insole and synthetic upper.

Looking toward the toe, the Load ‘n’ Launch pad is visible in green. A hinge is visible.

Slicing along the foot-axis, I exposed the side of the Load ‘n’ Launch. Notice two plastic pieces embedded in the foam and a series of springs.

Cutting the entire unit out of the sole, I exposed the metal and elastomeric springs. So there it is. The fine folks at APL have embedded springs into the sole of their Concept 3 shoe. I understand how a spring should increase the amount of energy returned when the forefoot compressed the sole, but in practice the technology did not seem to lead to higher jumps for me.