adidas adiZero Crazy Light

words & images // Zac Dubasik

Weighing in at a mere 9.8 ounces, the adiZero Crazy Light has grabbed the attention of the hoops sneaker world when it was announced this April. Not only did it break the 10-ounce barrier, it gave adidas claim to the lightest shoe in basketball. It shouldn’t come as a surprise that its creation didn’t happen over night, and that it took an entire team working on the project to bring it to fruition. Following the launch event, and my first opportunity to play in the Crazy Light, I had a chance to sit down with some key members of the adidas team that made this shoe a reality: Elysia Davis of the Sports Researcher adidas Innovation Team [aIT], Robbie Fuller, adidas Basketball Footwear Design, and Global Category Manager for Footwear of adidas Basketball, Jack Gray. We talked in-depth about the design, development and inspiration behind this groundbreaking sneaker.

Zac Dubasik: Could you talk about the starting point for the Crazy Light? Where’d the idea initially come from?

Elysia: We really tried to rethink the way we would construct a basketball shoe, starting with nothing, and then adding support and comfort elements until we got to a highly functioning basketball shoe. It started with one of these really minimal uppers that has pretty much nothing on it. We would run performance drills in something as minimal as that, really looking at which areas were working, and which needed more support. We’d use high-speed video and look at how materials were straining during lateral movements, and look at areas that needed reinforcing, and just kept building from there. It was a rework of how we construct a shoe.

How far back did that concept start?

Elysia: The concept that Lawrence [Norman, VP of adidas Global Basketball] and his team had, to come up with the lightest-weight basketball shoe ever, is probably five years or more old. Construction on this shoe would be two, to two-and-a-half years ago, when we started making the first pullovers in China and our lab in Portland.

[Turns to Robbie] Could you talk about your first sketches, and where the actual look of the shoe started to develop?

adidas adiZero Crazy Light - An In-Depth LookRobbie: The Innovation Team really set some great foundation for the project: the idea of doing more of a Sprintframe concept, the fact that the upper would be these seat belts almost, that come from the eyelets to the bottom, were definitely parts of the initial concept. So then they kind of handed over the baton – but we still worked super close together. With some of the first sketches, I knew for sure that I wanted to look at how to move the branding to more of a unique place. The idea was that, if you are going to come with something so brand new and so groundbreaking that you want to give it more of a unique icon. On an NBA court, typically we’re going to pop the branding, and it might get hidden with Pro Models and things like that. We wanted to have it in a unique way that supported the adiZero marker of modern branding: more horizontal. And it also goes along with the Rose point of view, which is the last thing you see is the back of him, so you get the stripes towards the back.

Secondly, there was a need for a little more of a horizontal line to the shoe, to give it a little more flow throughout. Obviously, it was going to increase some of the support as well. That was a marker, and once you had these vertical lines with a horizontal line, it started to have this web effect. I was literally at home sketching, and I was like, “Hey, SPRINTWEB.” That’s exactly what this thing looks like. You see webs in nature, and they’re really, really strong. Air, and all of nature’s elements try to take them out, but they can’t. They still stay there. They’re breathable, lightweight and strong. So, those were a couple of key things that happened once I moved on to the project.

One of the seemingly obvious ways to cut weight is to chop the collar off a shoe. But you didn’t do that here.

Robbie: When you are developing the lightest basketball shoe ever made, I think it’s even more impressive that we did it as a mid to a hi-top. The fact that it’s lighter than any shoe, no matter what – low or high – is pretty impressive. We wanted to guarantee that we had the right support, so we knew there was going to be certain heights to the tooling anyway. So, for this initial launch, we wanted to develop a mid, to a hi-top. In subsequent launches after this, you’ll see that we are looking at all ways to save weight on a basketball product.

What’s the difference between the two different insoles the shoe ships with?

Elysia: With every component on this shoe, we looked at every possible way to save weight. And an insole, or sockliner, is definitely an area that you can optimize. So, we gave two options. The first is an ultra-lightweight option, to kind of keeping with the theme of the shoe. If you want the lightest weight, quickest shoe ever, you would throw that sockliner in. And for some people that want a little bit more plush feeling on the bottom of your foot, you’ve got a little bit thicker option as well. It’s just being able to customize your shoes for the exact fit and feel you want.

Robbie: For the Crazy Light sockliner, it’s a brand new material that I don’t think we’ve ever used before. Really, really lightweight and perfed out. The reason we are able to use that is because of the construction of the SPRINTFRAME. Once you have the shoe, and take the sockliner out, you’ll see what’s called a Strobel board. What that means is that with a typical shoe, you have your midsole, and then you have the upper, and the upper has a Strobel board, and that is glued down to the foam. So, in between the foam, which is the cushioning part, and your foot, you end up having this almost trampoline of plywood that’s been glued together. So, what we were able to do was because of the stitching of the SPRINTFRAME to the upper, you don’t have to have any glue whatsoever. You have no trampoline, so to speak, or stiff material. So, you are standing directly on the foam. And that allows us to get the exact same amount of cushioning you would’ve gotten out of, for example, something that’s 30 mills. You can get that out of something that’s 24 mills, because it’s already so much softer. That’s why we can offer the Crazy Light sockliner, and make zero concessions for cushioning. And then, if you want to play five hours on a Saturday [laughs], you probably want to go with the Comfort one.adidas adiZero Crazy Light - An In-Depth Look Sketches

I just got the chance to play in these, and I found the cushioning to be much softer than I expected. Like chopping off the collar, cushioning seems to be another easy place to cut back on when trying to reduce weight. I thought it was noticeably softer than in the Rose shoes this season.

adidas adiZero Crazy Light - An In-Depth Look - Sprintframe

Elysia: We really wanted to follow through with not sacrificing anything when you take a lot of weight out of the shoe. You’re right, the forefoot cushioning is a lot better in this shoe, and it’s going to really cushion hard impacts. And it’s going to give you a soft feel when you are just standing in the shoe, so that step-in feel is a lot better as well.

Robbie: There were two things about this. We used premium sourcing. Not all coffee is the same; not all foam is the same. [laughs] We have one supplier whose base materials they provide us are superior. So we used them for this shoe. And secondly, we used sculpting in order to provide cushioning. You can really see that in the final shoe, and even in the earlier samples. [We knew there were areas] where it was alright to have more cushioning, and then you want to have a little more support [in other areas]. On the final shoe, the depth of the groove is really shallow in the front, and then goes to thicker, and then really thick in the back. You can have the ultimate in cushioning, but then when you get to the front, you need stability for slowing rollover . . . All I can say is what you’ve said. When you put them on, it feels so much softer than traditional adidas foams. And I would say, great. We’ve heard the athletes, and some of the testers loud and clear. It’s something we’ve known we needed to get better and better at. We see the Crazy Light as one of the first shoes that really shows that there is great cushioning in adidas products.

adidas adiZero Crazy Light - An In-Depth Look - Sprintframe Stitched Upper

Could you explain the decoupled heel, and the main grooves in the outsole?

Robbie: The outsole is very zone specific. We know that the highest wear areas are the medial side, along the edge, the lateral, along the edge, and the same with the heel. Generally, a rubber outsole – for ease of development and construction – is the same thickness everywhere. But that’s not what the wear patterns are; that’s not what the traction needs are. By having it thicker along the edge, and thinner through the midfoot, we’re able to cut weight without sacrificing any traction.

And then, you see these two pattern executions. This was derived from some of the initial concepts from Christian Tresser, the first aIT designer that was working on this shoe. He was using more of a rotational pattern for the pivot zone, and then came up with this really thin, new herringbone pattern that really limits the amount of surface area that you have. Less surface area, less dust. Dust is the enemy. It doesn’t have anywhere to stick. And because it’s so thin, it actually almost “cleans itself” in a lot of ways. Not literally. [laughs] Don’t expect to flip over the shoe and see that there’s no dust. But it just means that it’s really hard for the dust to collect. You’re never going to take wiping your soles out of the game, because it’s just something you do, like when you’re shooting free throws. What it means is your traction is going to go from amazing, to ridiculous.

adidas adiZero Crazy Light - An In-Depth LookElysia: As far as the decoupled nature of the bottom unit, it kind of follows through with the whole trend of the entire shoe, which is this decoupling, from the heel to the forefoot, but also from the medial side to the lateral side. So, if you are going to do a standard V-cut, you’re going to put most of your force on that medial side, and that decoupling allows you to plant and get ground contact on that medial side without having this lever pull you over. And the same if you do a cross-cut, or if you’re doing curvilinear running around the key, and you’re going to be planting on that lateral side. Both are important aspects of the shoe. And the same with heel strikers that need that decoupled heel for that exact same reason.

How was the decision made to use a stitching-based construction to secure the upper, and how does that benefit the overall shoe?

Elysia: Just looking at the upper, that’s 30-40 percent of the shoe’s weight in a traditional basketball shoe. One way that we reduced the weight was the SPRINTWEB, and really only putting the strength materials in the areas that it’s needed. The second way was taking out the whole heel portion of the upper, the glue layers to adhere the upper to the Strobel board, the Strobel board to the bottom unit, to the heel counter, and really reducing all the layers. So, now we have an upper that’s stitched to the heel counter, and so it’s just weight savings.

Robbie: You can imagine, it’s a complete rethink on how you make shoes. It’s retraining the factory, and new machines that you have to buy. It’s called a post stitch machine; it’s able to get inside and do the stitch. All of those things had to be considered and evaluated, and we decided, yes, we have to go this route. Why? Because it’s more than half an ounce. If we don’t do this, then we’re not going to be the lightest. It’s a really simple solution. We call it the Bounce construction. If you look at the Megabounce, Megabounce+, and all those shoes, they use a stitch to connect the upper to the tool. So we already had learnings along this path, but it hadn’t been applied to a lightweight goal; it’d been applied to an energy return goal.

How big of a challenge was finalizing the design and array of the SPRINTWEB? I see a lot of different versions in these samples and sketches.

Robbie: It was a huge challenge. It was like Edison with the light bulb. It doesn’t work, doesn’t work, doesn’t work, and finally we figured out one that works. It was just like that, working with our materials team over and over again, asking suppliers for little tweaks here and there. Multiple, multiple base meshes, versus multiple different synthetics and bonding them together. And finally, after all of that, we found one recipe that ended up exceeding all of our expectations. We have a goal of a certain amount of strength, that’s measured in newtons, it won’t tear off. And I’m glad to say that it not only hit that level, it actually went between 20 and 100 percent beating it. So, I know for sure that these are going to stay nice and tight to that textile base.

How does adiZero play into the bigger picture for the brand? Is it strictly performance?

Jack: adiZero is a huge initiative for us as a brand. Obviously, with the F50 in football, as well as adiZero in baseball, and the 5-Star is a good example of how we’re getting after it in American football. I think the biggest thing for us is with our one brand anthem right now, you really see the breadth of our brand. You have the ultimate lifestyle brand, with adidas Originals. And this was the perfect example for us to really talk about how light is right for the consumer. By incorporating our Originals team, they’ve taken the best of the SPRINTWEB and they’ve utilized that in the adidas Forum. They’ve re-engineered the Forum, utilizing an EVA outsole and midsole, and then come in and used the SPRINTWEB in the upper. We really are telling this full lightweight story within the brand, and really listening to the kids as to what they want, from the court to the street.

Do you think that this specific construction and the SPRINTWEB technology can apply across the whole basketball line?

Robbie: It applies to the lightweight benefit. So, yes. A lot of the products we make, we still want to be the lightest-weight brand. SPRINTWEB is a great innovation – it’s revolutionary. We are able to do it in just a minimal amount of layers: only two layers. And what’s cool about that is that it can be applied to all different kinds of designs and patterns, whether it’s in Originals, or other areas of the brand. I think you’ll continue to see that within the basketball category, and it’s a great tool that we can use on other sport categories.

Do you think there’s a long way to go in the quest for light weight? Or do you ever worry that there will be backlash, and people will start to perceive things as “too light?”

Elysia: I don’t think we can ever say that something is “too light.” I think you can differentiate something that performs well, in whatever construction you choose, versus something that doesn’t perform well. And I think you get that in any weight product. Our goal here is to first get the best-performing basketball shoes we can ever make. And at the same time, make them the lightest possible. And we always have that first goal, that performance goal, in mind. If we get to the point where we start sacrificing performance, then it’s not worthwhile. But I think still we have a long way to go to optimize technique, materials and construction to that point that we can still innovate for light weight. And I don’t think we’ll ever go back to the 700-gram [24.7 ounce] size 13 basketball shoe. We are past that as shoemakers, and the consumer is past that as someone who plays ball. So I don’t think we’ll ever go back, but I think we’ll still try to push that boundary.

Robbie: The coolest thing is that the machines that we use to test a lot of these shoes, they are unbiased. They have no idea if the shoe weighs one ounce, or a thousand ounces. So, it’s just, “Does it pass?” Does it have the tear strength; does it have the right ratio of inversion and eversion? Those are the things it tests, and if it passes, then yeah. Someone, hopefully us, is going to be able to make a one-ounce shoe. [laughs] Weight isn’t the issue; weight isn’t the enemy. There is no threshold where people are going to say it’s too light. They think that when they hold it, but they have a completely different opinion on what is too light when they play, and they don’t feel like they’ve sacrificed anything. They still feel cushioning, they still feel control, they feel support. And at that point, they’re like, “Wow! These feel great!”

Elysia: And there’s this perception of weight, and kind of, luxury. And that perception is something you have to get past. If I tell you that you’re going to have less weight holding you back, that you are going to have to jump with less weight pulling you back to the ground, no one can tell you that’s not desirable. So we’ll just keep pushing it.

Robbie: It’s a competitive advantage, and as far as I know, winning is always cool. [laughs] You never get made fun of for being first. And that’s the idea behind these. They are an absolute, guaranteed competitive advantage when you have them on. And that is going to lead to wins.

Available for pre-order now: adidas adiZero Crazy Light

adidas adiZero Crazy Light - An In-Depth Look adidas adiZero Crazy Light - An In-Depth Look adidas adiZero Crazy Light - An In-Depth Look