Footwear Insight

its logical end and co -founder Golden Harper believes people are beginning to understand the different needs in shoe tightness during running compared to other athletic pursuits. While a basket- ball shoe, for example needs to lock the foot down to keep from rolling off during violent lateral movements, running is different. "It is not the same movement," Harper says. "Running is about efficiency, relaxation, forward movement." Engineered Solutions New processes make creating efficient, relaxed uppers easier today than ever. Rather than sewing together layers of mate- rials with different properties, using liners or overlays to create structure, companies are engi- neering fabrics to have unique zones over different parts of the foot. "Back in the day, we might have 65 components in a shoe, now we have about eight," says Stockbridge. Knitting is the newest rage, and comes with big promises. "You can knit an upper in three dimensions, which is a huge thing in terms of improving fit and comfort," Stockbridge says. "It simplifies footwear. It weighs less. It's easier and quicker to make. It costs less. There's less waste. There's no negative." While all agree on the promise, knits do seem to have some nega- tives. "Knit shoes are the trend for wearability, but not any shoe has nailed it for performance and func- tionality," says Topher Gaylord, GM & SVP–Run at Under Armour. "A lot of knit uppers provide a great socklike feel, but the foot is swimming around. They might be nice for walking, but not what a real running shoe needs." Knits are also less breathable and can be stiff and rough to the touch. "Either knit is very supportive, but then it is stiff, or else it is soft — but having both in the same shoe is quite hard to achieve," says David Allemann, co-founder of On, which is sticking with the proven functionality of engineered mesh until knits improve. The majority of brands, how- ever, a re using k nit in some product. Many are in the second round of knit design and are now combining other materials and layers with the knit uppers to enhance foot-hold or create softer feel. The promise of one-piece uppers, created with no waste, seems at least a generation away. Knits are improving rapidly, how- ever, and fully-engineered, 3 -D knit uppers with dialed-in, custom zones should arrive soon. In the meantime, today's uppers, even with a few layers, are lighter, more flexible and more adaptive. Nothing Is Standard Beyond knowing where to hold and where to relax, good fit is further complicated by the huge variety of foot shapes, even at rest. Arch shape, instep height, toe length, heel width — all of these and more vary from runner to runner. White points out, for example, that the location of the flex point along the length of the foot can vary by up to 10mm for the same size foot, so designing a controlling strap to fall pre - cisely behind that point can be problematic. HOKA ONE ONE: Evo Mafate (facing page) The advanced Matryx weave allows Kevlar strands to be engineered into the fabric, providing structure around the midfoot that improves durability and lateral control on the trail without adding weight or reducing flexibility and breathability in this ultra-light, single-layer upper. BROOKS: Bedlam (top) To add control to its circular-knit upper, Brooks uses a reinforced burrito-wrap tongue to lock down the midfoot and provide more support on the medial side, enhances the engineered zones to better stretch or support where desired, and debuts a rib-knit collar that hugs the ankle with a sock-like fit. UNDER ARMOUR: HOVR Sonic (center) Creating uppers that complement shoe function, Under Armour uses an engineered flat knit weave and an inner mesh arch-wrap to produce a sportier ride in its high-performance HOVR Sonic model. In contrast, its luxury-model HOVR Phantom gets a stretchier circular knit upper with bra- and bike chamois-inspired Speedform molding wrapping the heel and arch. SKECHERS: GOrun 6 (bottom) Simplifying the upper to a single engi- neered layer, the compression flat knit on the sixth version of the GOrun is designed for the runner who wants to feel like there is nothing on their feet, with the slightest bit of control knitted into desired zones by altering the weave and the yarn. footwearinsight.com January/February 2018 ~ Footwear Insight • 59

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