There's a good chance that even those of you who aren't runners are familiar with Nike Free footwear, whether you wear them for other sports or training or as a go-to sneaker for your day-to-day activities. While Tobie Hatfield (Tinker's brother, for the uninitiated) had originally designed the articulated midsole based on the biomechanics of barefoot running, the shoes have been adapted for (and adopted by) anyone who spends time on their feet—in keeping with the Nike credo "if you have a body, then you're an athlete"—which is to say, everyone.

Of course, the concept of Natural Motion is a natural extension (so to speak) of Nike co-founder Bill Bowerman's seminal insight into performance footwear: that it should "provide protection and traction but minimal weight and zero distraction." Like most any design challenge, it's easier said than done: For more on the history and background of the Free—now in its tenth year, Nike recently unveiled the 2014 Collection—we had the chance to chat with Hatfield, Director of Athlete Innovations, on his personal journey, the inspiration behind the Free and what the future holds for Nike.

Core77: Let's start with a bit of your background—tell me a little bit about yourself and how you ended up at Nike.

Tobie Hatfield: Sure—I was a track athlete, grew up in the state of Oregon and knew Coach Bill Bowerman (I didn't know Phil Knight when he was an athlete). When I was a senior in high school, he actually made me my first pair of custom-made track spikes. At first, he X-rayed my feet to actually find out where my bony prominences are, underneath my foot, so he could re-drill the holes and put the spikes in the proper places just for my foot. Little did I know, at that time, he was already starting to teach me about innovation—about working with an athlete, listening to an athlete...

It's something that I look back on, even today, 23+ years later at Nike... but I didn't know I was going to be a footwear engineer, footwear designer, I really wanted to be a track coach—my dad was a track coach for 40+ years. After high school, I went to college, and then I [continued] pole-vaulting for a couple more years. I got into coaching, and I coached at the collegiate level.

During that time, Nike was recruiting me because I spoke Mandarin, because I was married at the time, and my wife is from Taiwan. They were always trying to get people to go overseas, to work with the factories, and knowing that I already spoke one of the languages would make it a bit easier.

But I denied that for a while until my dad came down with cancer—I'd been away from Oregon for about ten years at that time and felt like things were pulling me back to the state... like, well, if I'm going to go back, I might as well go ahead and see what Nike has to offer, so I accepted their offer to have some interviews. At the end of a week of many days of interviews, I was actually offered two jobs, and I took the one where I actually started learning about materials, which is perfect because [at the time] I didn't know much about shoes at all, let alone the ingredients of them.

A brief history of Nike Innovation: Cortez (1972), Nike Sock Racer (1985), Air Huarache (1991), Air Rift (1995), Air Presto (2000)

So that's where I started the first year, moving back to Portland, Oregon, and working here in Beaverton, at the headquarters, learning about materials. And then eventually they sent me over to Taiwan—which was great for my wife as well because she was from there)—and I started to learn how to make shoes in the factories there on a daily basis.

From there, I actually got into the engineering side, working on their advanced concepts—I actually helped open our first R&D facility in Asia. It happened to be in 1995 when we did that, a year out from the '96 Olympics in Atlanta. Knowing I was a track athlete, they asked me to get involved with revamping all of our track shoes for the '96 Olympics, which included working with our premier athlete for track and field at the time, Michael Johnson. It was an easy transition for me because I was a track and field athlete for so long and I knew how to make shoes, so now it was just about putting some creative thought into it. That's where how I got started started designing, working on track spikes, [including] the gold shoe for Michael Johnson in '96, in which he won his two gold medals and broke the world record.

That kind of just kicked off my creative design career here at Nike, and essentially I've just been doing that ever since. I'm kind of known as one of the guys who can work with athletes and understand them fairly well—it doesn't have to be track and field, it can be any sport—and apply some of the techniques I've developed over the years and it seems to work. That's pretty much how I ended up where I am today, as the Director of Athlete Innovation in the Nike Innovation Kitchen.

Out of curiosity, what was the other job you were offered?

I was offered [a position at] another program which was really just getting going then, the EKIN program—EKIN is 'Nike' spelled backwards—those are our tech reps, who are out in the field. They get to know what the products are all about and what the benefits are to the athlete, but it's nothing to do with creating the product. Once the products are created, the reps to go out there and talk to the retailers and talk to even consumers about the benefits of our shoes. (EKIN is still around today...)

The EKIN job they offered me was actually in San Antonio, Texas, which defeated the purpose of actually getting hired at Nike, because I wanted to spend some time with my dad here in Oregon. So I took the other job, which was here at the headquarters.

So what's your day-to-day schedule like these days?

(Laughs) Kind of like today: Meeting, to meeting, to meeting...

[But seriously,] we have certain things that we have to do as far as working with our sample room—we have a full-fledged sample room here, where we can make a shoe from soup to nuts, which is really important for us, because we want to keep that really close to us. So [I check on] projects that I have going through the sample room; I have daily meetings with pattern and footwear engineers in there, going over the projects, making sure that they're being done, done well, done on time, all that kind of stuff.

Then we have, what we like in design world here, is called 'little sessions,' which are not necessarily on the calendar, officially. [The Innovation Kitchen] is a studio atmosphere—there's no doors, no walls, so everything's pretty much out in the open—so one designer can look at another designer or a developer, and look to see what's on their desk, and that inspires us, helps us ask questions, and [allows us to] see what's going on, if what they're doing over there could apply really well to what I'm doing. So we have these little sessions where we come in and see a designer, or engineer, or developer, and basically we just start talking. Those are really really important for us, so we have a lot of those every day.

And then of course we have athletes come in, or we go see them—Phil Knight always told us that it's so important to listen to the voice of the athlete, and it's so true, and that's what Bowerman was teaching me, when he was X-raying my feet [when I was] at South Eugene High School. It was great—we still employ those techniques and strategy for innovation today, and Bowerman is still the spirit that resides within the Innovation Kitchen. He started in his wife's kitchen, and that's really important to us.

Bill Bowerman

Right, the origin of the waffle sole is well-known design lore; how literally should we take the term "Innovation Kitchen," and what does it connote?

Yeah, I think the kitchen has a lot of great connotations for us. It's true that Bill started in his wife's kitchen and he ruined not only his wife's waffle iron but several of his wife's appliances, and that's why eventually she kicked him out of the kitchen and he had his own cobbling shop after that.

But if you think of chefs, whether it's a chef in Paris or a chef in New York—or even a chef here in Portland, Oregon—they're very creative and they work with ingredients. They experiment a lot on new kinds of foods by combining other foods, right? So in our Innovation Kitchen, if we start a project and we have a big pot, and we put in a little ingredient here and a little ingredient there, and we stir it around and then we taste-test it, or in our case, we wear-test it. Sometimes it doesn't taste so good and we have to throw the batch out and start over; other times it would be a matter of tweaking the recipe until we got it right.

Listening to the voice of the athlete gives us a lot of information that, oh yeah, that makes sense. And then we go back and start gathering ingredients, and we see what comes out. And hopefully we hit a home run, like we did with Nike Free.

Moving on to the Free, can you trace the lineage of the shoe? I know it's the tenth anniversary this year, since it was debuted in 2004; how long had it been in the works at that point?

Well the idea of Free itself really started back in 2001, even though we released it in August of 2004. Again, we were listening to the voice of the athlete, but it's not just the athlete, it's the athlete's trainers, coaches. In this case, [track and field coach] Vin Lananna at Stanford University was talking about his success—part of a coach's success has to do with how healthy his athletes are and he just felt like his athletes were just a bit healthier than some of the athletes on other teams, which he attributed to barefoot running. He didn't have any scientific proof, he just had what was in front of him, what was happening.

And so, the "A-Ha" moment came to us, that the problem was that not everybody has a nice pristine golf course, like Stanford does, on their campus, that they can run on, grass-wise. [But] what if you could take that nice green grass with you everywhere? In other words, the great thing about shoes that we know, for sure, is that they protect you against certain dangerous things, that could you know impale your foot on; the heat, the cold; mud... Shoes protect you from all of that, and that's great. But could we protect and allow the foot to be more barefoot-like in motion at the same time?

We expressed that to Vin, and he said, "Dang, ... that, if you could do that, that would be awesome." So that's what we set out to do. And before we even designed anything, it was critical was to understand the foot itself, while it was in motion, because we had to create a gold standard that you could compare back to, when you do scientific research, to see if a prototype is actually behaving the same as when it doesn't have anything on it, when it's "not shod," as we would call it. We [spent] the first six months gaining an understanding of the foot. Only when we understood the foot did we start to design.

[Which brings us to] the ice-cube tray analogy... we knew we needed to break up the sole, it couldn't be a slab of foam any more—it had to be articulated, so how do you do that? Well, I was thinking of ice cube trays, how when you have a flexible ice cube tray, how it breaks the ice up into segments, especially when you twist it on both ends. And so when we were thinking about making the molds for our foam piece, we thought about putting blades in there, criss-crossed just like blades in an ice cube tray, especially a metal one. And that's essentially what we did, and it worked really well.

Can you elaborate on the ten-point scale, from barefoot to a normal or traditional running shoe?

Well, the one thing that we did know at that time, was that we created the gold standard in the foot, so we knew what the measurements on the foot were, and we called that 'zero'—literally ground zero. And then our traditional shoes that were already around, we can go back and measure what those were compared to the bare foot. So if you established your bookends, you have some guidelines, but we just didn't know how far apart they were until we started measuring.

Once we knew where the barefoot and our traditional footwear were [in relation to each other], then there was the thought, "Where do we want to start in between? Do we want to start closer to barefoot, do we want to start closer to..." I think it was literally in a meeting one time, and I said, "Look, why don't we just start in the middle? If we call barefoot zero and traditional ten, let's just start at a five, halfway between where you're at with barefoot and where you're at with tradition." That's basically was how the Nike Free spectrum was created, and we knew that then we could either go up and down [from 5.0] as well, because we had the testing protocol to be able to do that. We can take any shoe in the world and run it through that testing protocol and tell you where it would fall in the Nike spectrum.

However, at that point, we weren't quite sure whether that was something that was important to tell the consumers about; it was more just for us to know where we were at. Once we had a prototype and we were trying to hit a 5.0, in the middle, and now that we had this scale, this spectrum, we were able to know if we hit that or not—so that was originally intended for more internal [reference].

But then, as I was thinking about it more, [I thought,] wouldn't consumers and athletes want to know where they're at as well, if they're going to start on a barefoot training program? I think they would want to know because then you want to work on a progressive nature of getting down further if you were going to start at a certain point. And that's when we started labelling them with the numbers on the shoes.

The original 2004 Nike Free 5.0

Do you plan on exploring other numbers on the scale, or is it intended more as a reference?

Yeah, we're always learning [more] about the body in motion. There's a gap between zero and three—we don't have a two or a one—but it's not because we didn't want to, [it's that] we didn't want to throw something in there just because certain numbers didn't have any shoes next to them yet. [Note: The 2014 collection, which was released nearly concurrently with this conversation, marks the release of the first-ever Nike Free 1.0.]

It only comes when you have the research to really back it up and if it's important to the athlete, and we can tell the athlete how they're going to gain from the shoe. So it's just about the research, [uncovering] information that is beneficial to the athlete... we are still learning and we're still trying to figure out what that all means for the athlete.

Originally, we started off with a five, followed by a four, and then we went down to a three. Because all of our research was very well-defined between a three and a five, so we knew that those numbers were right in the zone. We dropped the four for a little bit because the way that we were designing and constructing it, it was hard for the consumer to actually feel the difference between a five and the four. But they could feel the difference between a five and a three. So a two-number jump was something that was very noticeable, perception-wise. We could measure it, but that doesn't mean that the consumer can feel it.

The four came back once we had new siping patterns, more understanding of the body, and what the four actually means, and now we've reintroduced it because perception is greater now than [it was] earlier on. So new technology, new materials and new information allows us to put that back in.

Conversely, the Nike Free has been adopted not only by athletes, but also by a broader audience as well. But driving force behind what the Innovation Kitchen does remains performance-oriented...

It always starts with the performance... but the learnings for Nike Free are being applied across the board in almost all of our other categories, our other products, um, even in apparel and equipment, I mean... The whole idea of natural motion, and working with the body, letting the body do its thing, is something that all [of our] designers are conscious of, pretty much every day now since we've had Free. So it permeates everything that we do here at Nike—you're going to see it a lot, the influence of Nike Free across the board.

Selections from the 2014 Collection

Do you think there's a limit to how scientific research can improve performance?

I think the best way I can answer that question is that um I've been asked before, 'Do I ever have what's equivalent of 'writer's block,'—when you can't think of something creative or something like that. I didn't know how to answer that at the beginning, but then I thought about it and my eventual answer was "No, I don't think I'll ever have writer's block." And the reason is that the answer always lies within the athlete, and so it's my job as an innovator to really pull that out, to extract it and then put that in a product form.

Athlete insights are always going to be the center of our design approach. And so that is something that will always tell me that as long as there are athletes out there—and if you have a body, then you're an athlete, as Bill Bowerman always said—then there is no limit. You know, people thought there was a limit to how fast a human being could run the 100 meters, and even scientists said it's not possible to run under 9.7 seconds, and the 100-meter record now is a 9.58.

From the beginning of time, it's a matter of humans progressing at different paces and I think we'll continue to see that in our business as well. Again, both for me and for Nike as a company, it's always about the athlete, and we're going to continue to extract information from them. It's really exciting to think what can happen in the future with these athletes.

The one thing that we say around here is that there's no finish line. There's really no limits in our sights and we feel really, really excited about that.