More than anything else, running is a sport that places heavy reliance on your chosen footwear. Like runners themselves, manufacturers have been fiercely competitive, producing faster, light and more durable shoes with each passing season. The real core of the running shoe has always been the midsole.
It’s the core around which everything else is built, with a direct influence over the overall stability and cushioning feel of every pair of shoes.
The midsole must be both durable and flexible. It must be highly resilient to temperature, weight and humidity fluctuations. It must be highly stable as the backbone of the whole shoe, and also be able to absorb the impact of thousands of steps.
When running as a sport and leisure activity first took off in a big way in the 1970s, the material of choice for midsoles was EVA (ethylene-vinyl acetate) foam. It dominated the scene for many years thanks to its relatively light weight and flexibility.
However, EVA has a few disadvantages for serious long-distance running. It is not very durable, and will gradually flatten out with use, losing its rebound and cushioning ability. It is also quite sensitive to temperature extremes, hardening in cold climates.
There were attempts to broaden the lifespan of EVA by blending them with olefin-based polymers such as ENGAGE™ Polyolefin Elastomers (POEs) to overcome their shortcomings in flexibility and resilience, but over the last decade, newly developed materials have come to surpass EVA.
When it set out to build its own line of revolutionary running shoes, Under Armour wanted to find an industry partner in developing a performance foam that is as lightweight as EVA but much more durable under a wide range of temperatures and usage conditions.
After much testing, the sports apparel maker decided that Dow INFUSE™ Olefin Block Copolymers (OBCs) was the key to the equation. Blending INFUSE™ into Under Armour’s Charged midsole formula provided excellent resilience and softness while not compromising on lightweight qualities. INFUSE™ proves to be superior to the EVA-POE blended foam. Thanks to the resilience and durability of INFUSE™, Under Armour’s running shoes are one of the longest lasting currently available.
A superior midsole technology that is lighter, lasts longer and performs better, the application of Dow INFUSE™ OBCs in Under Armour’s athletic shoes has helped to differentiate the sports brand from competitors.
With a high rate of rebound and excellent bonding characteristics, the material in not only ideal for cushioning and support in a running shoe, it is a consistent backbone that all other components of a shoe can be securely adhered to. As far as engineered synthetic materials go, the Dow INFUSE™ OBCs in Under Armour’s Charged cushioning system is one of the most consistent ever manufactured.
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