The science of running seems to have hit the ground, well, running: Yesterday saw the introduction of a shoe that boasts 648 possible combinations of components designed to prevent injuries and maximize performance.

The idea, says Santa Cruz, Calif.-based Somnio Running, is to pair a shoe to each runner’s unique biomechanics, compensating for everything from high arches to bow legs. The left and right don’t even have to match. “Every runner is different, and we believe that every pair of running shoes should be different,” said Somnio founder Sean Sullivan in a statement. His company’s pitch: “Don’t just sell shoes. Solve problems.”

To help design the shoe, Sullivan hired Andy Pruit, an internationally known athletic trainer at the Boulder Center for Sports Medicine. In addition to adjustable cushioning and insole shape, they wanted a shoe that cut down on unnecessary side-to-side motion. So they built a device that projects a laser up a runner’s leg that fitters can use to figure out which Somnio components to add. Inserts tweak the foot’s position in the shoe and, in turn, change the angle of the lower leg.

A choice of three base model options – for both men and women – with interchangeable footbeds, cushions and wedges will set you back around $125, as well as several minutes for the full fit process.

But will strapping cutting-edge technology to your foot really increase performance, and decrease injuries? “It’s fine and dandy to have hundreds of possibilities,” says Benno Nigg, co-director of the human performance laboratory at the University of Calgary, “but how do we decide how to put them together?” Even though Somnio trains their shoe sellers to carry out the custom fits, Nigg worries that decades of biomechanical research still haven’t led to any clear guidelines: “Nobody really knows what is optimal for you.” 

In fact, in an homage to the day that the Somnio was introduced – June 1, also National Go Barefoot Day – Nigg says the closest thing to the optimal shoe is no shoe at all. He believes that the unnatural guidance provided by shoes like the Somnio could weaken muscles and actually make a runner more prone to injury.

“I advocate real barefoot running,” says Nigg. Of all the muscles around the foot, only the calf and inner shin are left to do work. “The rest is done by the shoe,” Nigg says, adding that the more supportive the shoe, the less human labor is required. “Then if you take off your shoes, the muscles are not strong enough to stabilize you.”

This also means that it takes time to strengthen these underworked muscles to the point that running sans shoes is comfortable. Of course, landing barefoot on a shard of glass or recently discarded cigarette butt may never be that comfortable.

Image of courtesy of Somnio Running