Super Yarn: Nike's Footwear Material for the Future
Yarn. Not just your run-of-the-mill, quilt-shop-style yarn. Nike has scientifically engineered super yarn—which they've dubbed Flyknit—to lead its new wave of performance footwear, including its lucrative running shoe lines and World Cup soccer footwear.
What started in running shoes with a simple effort at crafting shoes made with this sock-like feel has spun out into something more. Now Flyknit shows up in a variety of training and running lines and has recently expanded beyond that into basketball shoes—the Kobe 9 super-hightop is Flyknit. But the biggest new change comes ahead of the June World Cup, as Nike’s two latest soccer cleats, the brand-new Magista and the revamped Mercurial Superfly, both feature engineered yarn.
With Flyknit on the asphalt, the hardwood and the turf, expect yarn to continue to wrap its way around more Nike shoes.
Flyknit debuted in 2012. While yarn generally lacks structure and durability, folks love its feel. Flyknit micro-engineers static properties in pliable materials, creating products that save the company money and improve performance. The one-piece engineered upper builds from single strands, providing a virtually seamless upper and reducing material layering and costly waste. This saves cash. Plus, you get the feel of a sock with the function of a shoe. That solidifies performance.
“The way we think about Flyknit is strong and light,” Max Blau, Nike’s vice president of football footwear, tells Edge.
But not all Flyknit is created equal. “We had to adapt the technology for football [i.e. soccer],” Phil McCartney, Nike’s vice president of football footwear, tells Edge. “There is no technology that gets the foot closer to the ball than Flyknit. It allows us to eliminate distraction when players feel the boot rubbing the foot and ankle.”
The Magista was designed for a player needing touch on the ball, so the yarn itself contains loft and texture. The Mecurial, launched just weeks later as the signature boot for Cristiano Ronaldo, was built for speed, with an especially thin knit.
“The easiest way to think about it is the knit upper is a three-ply application,” Blau says. “There are different ways to knit. The Magista is five [layers]; the Mercurial three. It has the rigidity we needed, but [also] the reductive feel we needed.”
“It is the same technology,” Dennis Dekovic, Nike’s design director, tells Edge regarding Flyknit lines, “but the application is different. The design is very different. What is made is specific.”
To keep the water out without adding layers, Nike has a treatment on the surface thinner than a sheet of paper. This 3D texturing is a first for Flyknit and opens the door for all kinds of outdoor footwear applications, while giving a soccer cleat added friction to increase ball control. The Flyknit yarns themselves don’t retain water.
Also new for the neon yellow Magista, Nike included 10 Brio cables tunneled into the knit to lock the shoe’s upper to the outsole, a way to provide strength and support without adding bulky materials. The Mercurial also has Brio cables.
During a press event, Iniesta said the “fabric, the knit, the sock” all increase his comfort, fitting his foot “like having a glove.”
By nature the yarns reduce weight, dropping the Magista to 195 grams and the Mercurial to 190, but those aren’t goals to be met, Blau says, just a feature on the path toward increasing functionality.
As Flyknit applications have grown—the Mercurial, released in April, had been in the works for nearly four years—Nike designers have been able to learn its benefits across multiple uses. “The technology is the same, but how we apply it is very different,” Blau says.
And that goes for another Spring 2014 release from Nike, the latest Free line, which includes Flyknit, one of a few running/training offerings. The engineered yarn for running allows extra breathability and stretch in some areas, but the diversity to weave in support where needed. Designers can micro-engineer tighter zones—sometimes with thin cables—in precise support-needing locations.
For Kobe’s 2013 release, Nike designer Eric Avar says Flyknit gave him the ability to engineer similar to the design of a spider web, with tension and strength just where he needed.
Just think: In 2014 it appears yarn, albeit engineered yarn, sits as the new frontier of performance materials.
Tim Newcomb covers stadiums, design and gear for Sports Illustrated. Follow him on Twitter at @tdnewcomb.