You know the shoes Ruth Chepngetich and Eilud Kipchoge wear, partially responsible for some of the fastest marathon times ever recorded? Those are called super shoes. They鈥檙e thick-soled, with ultralight, hyper-responsive foam midsoles embedded with carbon-fiber plates. Think of super trainers as the more easygoing but still light and responsive cousins of super shoes. We sliced one open at our gear lab in Colorado to find out what makes them go zoom.
Midsole Foam
At the heart of every super shoe and super trainer is a thick slab of high-tech foam that鈥檚 lighter, softer, and bouncier than any other midsole material to date. It鈥檚 created by a process called supercritical foaming that combines heat, pressure, and liquid gas to infuse bubbles into elastic polymers like PEBA, TPEE, and ATPU. The resulting midsoles deliver plush cushioning and trampoline-like 颅rebound, but are squishy and unstable, requiring a balanced, 颅powerful stride to optimize performance.
Super shoes have full stacks of these soft, bouncy foams. However, many super trainers, like the shown here, use a combination of foams鈥攕ofter on top of firmer鈥攖o provide an energetic feel while delivering the kind of stride-supporting ride more suitable for a training shoe. The step-in feels soft underfoot, but when put through a heel-compression
test used to at the 国产吃瓜黑料 Lab, the Deviate Nitro 3 super trainer was less squishy than all the racers we tested.
Traditional trainers use foams that are firmer and more supportive or are soft but not as bouncy鈥攗sually EVA or an EVA blend鈥攄elivering a more grounded, rolling ride.
Plate
All super shoes have a rigid, curved carbon-fiber plate embedded in the midsole. While many assume that this acts like a spring, research has shown that its role is to moderate the foam鈥檚 squish and channel its rebound, reducing energy loss and facilitating powerful push-offs.
Super trainers also typically have an embedded plate, but one with more flex. While rigid plates provide the most pop, they also dictate how the shoe rolls forward and can negatively alter the stride. A super trainer鈥檚 plate鈥攍ike the one in the Deviate Nitro 3, made of a carbon-composite weave with a forked forefoot shape鈥斅璦ccommodates a wider range of paces and strides and is less prone to bouncing feet in unproductive directions when form deteriorates from fatigue.
Plates differ in flex, shape, and location within the foam. This 颅affects how the foot rolls and interacts with the ground, and each feels different when combined with a runner鈥檚 unique stride.
Rocker
With the thick foam in many of today鈥檚 running shoes, the sole no longer flexes much at the ball of the foot. Instead, the foam鈥檚 height allows designers to cut away mass under the toe, creating a rocker shape. Rather than enabling the foot to flex as it moves through the stride, that shape allows the runner to roll off the toe while the foot remains in a neutral position. The rocker鈥檚 starting point, slope, and relationship to the plate all affect the shoe鈥檚 ride. In our measurements, the Deviate Nitro 3鈥檚 rocker started 8 percent later (closer to the toe) than the rocker on Puma鈥檚 Fast-R Nitro 2 racing super shoe, providing a stabler forefoot stance before rolling forward.
Outsole
A three-millimeter-thick rubber outsole covers more than 90 percent of the forefoot and all contact areas of the heel on the 颅Deviate Nitro 3. This provides better grip and durability than the sole of a racer, which needs to be as light as possible and so has rubber only in small, optimized zones.
Upper
Super-shoe racers have minimal uppers with scant padding and strong, secure grip to hold the foot in place at speed. A super trainer鈥檚 upper is more plush and durable but still lightweight, thanks to strategically placed fabrics that stretch, breathe, or 颅support as needed.
Featured Super Trainer
Puma Deviate Nitro 3听
Weight: 10.1 oz (men鈥檚)
Stack Height: 39 mm (heel); 29 mm (forefoot)
Drop: 10 mm
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