Making a sneaker usually involves quite a bit of work and time, which is one reason most shoe manufacturing happens in places with cheaper labor than in the U.S., such as Vietnam or China. The process also creates waste, since every time a piece of a shoe is cut out, extra pieces are left behind. But if the shoe is knitted instead of sewn, suddenly there's almost no wasted material—and all of the work can be done by a machine.
The latest soccer cleats from Adidas are two examples of the new manufacturing process, with uppers entirely knitted from front to back. Billed as the “world’s first knitted football boot,” the Samba Primeknit was released at the end of February, just days before the Primeknit FS, a knitted sock-and-cleat combo that fits all the way up the calf.
“The Primeknit construction uses the latest design tools and a seamless engineering construction that allows us to digitally knit the entire upper in one continuous piece,” says James Carnes, global creative director for sport performance design at Adidas. “Traditionally, sports shoes are built from several different pieces, which can mean excess material.”
For athletes, the knitted sneakers are a way to get support and protection while wearing something that feels more like a very lightweight sock than a shoe. "Knitting allows us to fine-tune the exact amount of flexibility and support needed in every part of the shoe," explains Carnes. "[It] combines the comfort and responsiveness of playing barefoot with the protection of a traditional design."
Adidas isn’t alone in using a version of this technique. Nike also has a line of knitted shoes called the Flyknit, lightweight sneakers that reduce the typical waste of making a running shoe by about 80%. Both companies have been competing to release new versions of knitted shoes ahead of each other; Nike's own hybrid sock and cleat was announced just after the one from Adidas.
In 2012, both companies released their first knitted shoes, and that time Nike was first—it actually sued Adidas for patent infringement when the German company came out with a similar shoe months later. But Adidas says that the timing was just an example of the same idea bubbling to the surface in different parts of the market because both manufacturers were searching for innovative and more sustainable techniques.
"We looked at how we could go from a modular approach with footwear where you cut all the pieces and then put it together to something more innovative like knitting," Carnes says.
Both companies plan to keep building their knitted lines, with several more releases planned for later this year. While they're already netting savings in wasted material, it's not clear yet if this portion of their manufacturing will grow enough to bring back more local factories. Maybe one day machines will just take over completely.