adidas Response Trail Boost Women's Running Shoes Textile upper - Durable, adaptive and comfortable on the foot. Synthetic Overlays - Provide structure. Triple Strap Support - Supports and cradles the midfoot for comfort through the miles. Boost Midsole - Alleviates impact shock and propels each step forward. Aggressive Outsole Lug Design - Deep set with a repeating patter for optimal traction across a range of surfaces, performing just as comfortably on loose rocky terrain as hard dry ground.