The combination of thoughtful support innovations and a soft aggressive off-road tread make The North Face Women's Arnuva 100 TR trail running shoe an excellent pick for ultra distance athletes who tend hit their personal bests off asphalt. The Women's Arnuva 100 TR features an incredibly lightweight and supportive dual density compression molded EVA midsole above a high traction Tenacious Grip rubber outsole but everything is assisted with a rear foot compression cage for added stability. The North Face also added X-2™ polymer compounds in the midsoles to dampen vibrations and add resiliency that won't "pack in" as quickly as other cushy endurance shoes. Another nice extra inside the shoe is a Sure Grip heel lining panel that minimizes friction and helps eliminate heel slip. Beneath the Arnuva 100 TR is The North Face Tenacous Grip rubber outsole an innovative compound that grips exceptionally well off-road even in a variety of weather and temperature conditions.