From Hansons-Brooks runner Desiree Linden becoming the first American female to win in Boston in 33 years to Japanese Yuki Kawauchi stealing our hearts and first place in the Men’s Open division and a virtually-unknown runner securing a podium finish, this year’s Boston Marathon has been anything but mediocre. Although the race is long over, we can’t help but be excited about all the stories, products and innovations coming out of the annual event.
Prior to the marathon, we met with Nike to get a sneak peek at their latest concept in performance footwear, a 3D-printed textile upper. The Nike Flyprint uppers are produced through solid deposit modeling (SDM) which takes a TPU filament and unwinds it from a coil, melts it and then lays it down in layers. This process allows designers to translate athlete data into new textile geometries to improve runner performance.
But before this concept came about, Nike designers needed to figure out what worked well with their shoes and what didn’t. In 2017, Olympic gold medalist Eliud Kipchoge donned Nike’s Zoom Vaporflys to tackle the BMW Berlin Marathon. At around mile 24, the Kenyan runner chased down the lead and went on to win with a time of 2:03:32.
Following his win, the Nike Zoom Vaporfly Elite and Nike Zoom Vaporfly 4% became the most dominant shoes on the marathon circuit. Yet, similar to the weather conditions at the 2018 Boston Marathon, Kipchoge had to deal with heavy rain during the race and felt that his Nike’s absorbed water that added weight to his run. Working with the gold medalist, Nike designers decided to transform the upper while maintaining its tooling.
It was then that they brought back the idea of a 3D upper which they had previously experimented with but never implemented. With that, the Nike Flyprint was born and taken to Kipchoge for testing in 2018. During the first, rapid-fire prototyping phase, the Kenyan wrote out specific points of improvement for Version D of the shoes which included a need for a tighter weave and firmer material in front to protect the forefoot.
To create the shoe, the process begins by capturing athlete data that is calculated through computational design tools to affirm the ideal composition of the material. That information is then used to produce the final textile. This means that Flyprint textile outputs can be wholly unique to athlete or function. Designers can go in and tweak the prototype and reproduce it 16 times quicker than with previous manufacturing methods.
For Kipchoge, that meant his improvements were done within hours of his response and the new shoe was created almost immediately. The longest part of the process was shipping version E back to Kenya (nine days).
“One interesting benefit of 3D textiles over traditional 2D fabrics is the increased dynamism made possible by adding an interconnection beyond a warp and weft; an advantage of Flyprint textiles comes in the fused nature of the material,” Nike. “For example, whereas in a knit or woven textile there is frictional resistance between the interlaced (warp and weft) yarns, in a printed textile, due to its fused intersections, there is greater potential for precision-tuned containment. It is also lighter and more breathable than Nike’s previously employed textiles.”
When it comes to increasing runner speed, the Flyprint textile doesn’t absorb water like most other textiles so they are much lighter when running in wet conditions. Specifically for Kipchoge, the new uppers proved to be 11 grams lighter than the Zoom Vaporflys that he wore in Berlin. After another round of testing, the team settled on Version F of the shoes which Kipchoge will wear at this year’s London Marathon on April 22. The Olympian’s thoughts after testing out the Nike Zoom Vaporfly Elite Flyprints? He felt like he was “actually” flying. Enough said.