It wasn’t until James Carnes saw a rough sketch of a strange running shoe—the sole dotted with rounded, angled blades—that he thought the concept would actually work. "We’re taking a rigid and stiff material and making it look soft and elegant," says Carnes, the head of global design for Adidas. "That’s hard. This was something we always wanted but didn’t think we could get."
It took a few years, but that drawing is now a shoe. Yesterday, Adidas launched the Springblade, which goes on sale August 1. At $180, it’s the company’s most expensive running shoe. It’s also one of its most high-tech footware products. The 16 blades, strips of high-tech polymer that resemble the outstretched legs of a cheetah in full stride, are designed to work like individual springs. When they bounce back, unlike the soles of other shoes claiming similar properties, Carnes says, they propel a runner forward. Adidas is hoping that the distinctive blades become not only a staple of its running shoes but a stylish silhouette for everyday models as well.
The company could certainly use a hit running shoe. In May, Adidas ranked fourth in the crowded category, with 7.4% market share (down from 8.2% last year), compared to Nike’s estimated 43%. Penetrating that dominance remains a challenge, but recent advances in computer-assisted design and plastics are allowing Adidas and others to introduce new designs and technology, improving their chances of getting noticed and winning converts. Earlier this year, we explored Reebok’s approach, a polarizing design called the ATV 19+. Its oversized nodules were inspired by the knobby wheels on an all-terrain vehicle and built for off-road running, a new category Reebok hopes to build.
Engineers at Adidas have been working on shoes that exploit a runner’s energy at least since the early 1990s, Carnes says. To that end, they’re obsessed with race cars—Formula 1, since Adidas is based in Germany (the U.S. headquarters is in Portland). "This project comes out of looking at what happens to the energy a race car uses when it has to go around a corner," Carnes says. "Some of our brainy engineers started to think about how to harness the energy you push into a shoe when you land and not only re-use it but give it a specific direction."
Instead of adding a stiff flexing material to the mid-sole, which Adidas and others have done, the researchers broke the sole into individual pieces, hard-plastic spring blades. They’re longer than cleats, offer more give, and they’re positioned at a front-to-back angle. "Typically, if you get any energy coming back from the landing impact in a shoe, it goes back up," says Carnes. "This is designed so that when you push down, the blades help propel you forward."
The blades act like a tight suspension system, but researchers knew no one would buy shoes that felt rigid. They had to be high-performance and comfortable. Adidas wanted that elusive hybrid, the seemingly impossible marriage of a Formula-1 car and a 1950s Cadillac ("the pinnacle of comfort," Carnes says). Except in shoes. The development team sent test models to runners in Germany, the United States, and Asia who logged thousands of miles and provided feedback.
Meanwhile, Carnes wrestled with how to make the radical new look more appealing. How to tell the technical story through design. "We wanted to communicate this idea of propulsion and convey that your foot is floating above the ground," he says. So his team rounded the edges of the blades, giving them a softer appearance, and capped them with colorful tips, a playful touch. And because the rest of the spring is an almost translucent material, the shoe offers a hint of hovering above the ground. In short, Carnes celebrated the blades.
"Like with any good new thing, there’s an emotional reaction," he says. "That should be something familiar and a little bit provocative."