The guts of the shoe were a little trickier. Making running shoes is a lot like baking, says Arnaud Dabir, a project manager at Veja who worked with material scientists on the shoe. Each component is a precise mix of ingredients that must blend together for the end product to work. “Sometimes innovation isn’t inventing something new, it’s re-thinking thoroughly established processes,” he says. “Think of a gluten free chocolate cake—you take off a few classical ingredients and add new ones. In the end you still have a chocolate cake, as good as or better than the other ones, but made in a different way.”
There’s the outsole, the hard rubber exterior that provides durability and grip; and the inner sole, a firmer insert that gives structure to the shoe and cradles the foot. Sandwiched between the two is the midsole, the cushy layer of foam that provides support, absorbs impact, and gives the shoe a springiness. All of these components are commonly made from plastic, and every company has its own tightly held recipe for its foam’s fit and feel. The secrecy is understandable—a slight tweak to the formula can result in major energy savings and faster times for runners.
The Condor is less performance-based than something like Nike’s marathon-ready kicks, which meant Veja could experiment with some of the materials in its sole. Kopp says Veja’s material scientists spent three years searching for a mix of ingredients that would create a strong outsole that wasn’t pure synthetic rubber. In the beginning, they tried using 100 percent wild rubber tapped from the Amazon, but found the shoe was too heavy. Adding air to the natural latex made it lighter but far less resilient. “The sole would last for five runs and then it would give into the weight,” Kopp explains. Veja landed on a mixture of 30 percent wild rubber, 39 percent synthetic rubber, and 31 percent rice husk that makes the sole light but firm.
The midsole, too, is a combination of bio-based and synthetic materials. Fifty-five percent of the midsole is made from regular EVA—a modern, if environmentally destructive, marvel of material science known for its lightweight bounciness. For the other half, Veja created a bio-based foam made from banana oil (for flexibility), rice husk (for firmness), and sugarcane, the latter of which is quickly becoming a common replacement for petroleum-based materials like EVA. “What’s great about sugarcane is that it’s not different than the regular EVA,” Dabir says. “We have the same benefits and limitations.” For the insole, Veja concocted a mixture of regular EVA, jute, wild rubber, recycled plastic bottles, and recycled EVA that comes from the scraps generated during production. “In the recycling process, the EVA loses a part of its qualities, so to maintain the high level of performance, we limited its share to 8 percent,” Dabir added.