Most of us want running shoes that help us run faster and longer. But if you’re a hardcore runner, you might be looking for a way to make it more difficult to put one foot in front of the other.
That’s why people frequent Sand Dune Park in Southern California, a giant hill that’s–you guessed it–made of sand. It’s a popular workout spot for professional athletes like Kobe Bryant and Kevin Durant because running on sand is so damn hard.
Sand Dune Park is the inspiration behind a new shoe concept Grit that aims to give wearers the training benefits of running on sand wherever you are. Designed by Art Center College of Design recent graduate Aarish Netarwala in response to a prompt from Adidas asking student designers to imagine the future of sports, the 3D-printed shoe is composed of complex lattices that provide support where you need it, and collapse when you don’t, forcing the wearers to expend more energy as they’re running.
To create the prototype, Netarwala started by simply attaching pouches of granular materials like magnetic sand to the bottom of his running shoes, and trying to run on them. But there was a problem: While the sand certainly made it harder to run, it also meant that there was a real danger Netarwala would roll his ankle because the shoes were so unstable. So instead, Netarwala tried a 3D-printed latticework–with a denser pattern on the heel for stability and a collapsible pattern near the ball of the foot to make it difficult to push off–which worked much better.
From there, he created a prototype where the 3D-printed latticework, made of a thermoplastic elastomer, wraps entirely around the shoe. The shoe is composed of two pieces, the 3D-printed shell and a sock that slips inside. Eventually, Netarwala imagines personalized shoes based on each person’s running gait, with the densest latticework in whatever part of the foot the runner tends to land on most.
Grit is a rough concept and would need extensive testing and manufacturing partners to become a real product. (Netarwala says he is not looking for partners.) There is a reason that no major shoe manufacturer has created a shoe like it yet: It’s extremely difficult to create something that makes an athlete’s body less stable but is still safe to use.