The Nike Structure 24 has you ready to hit the road. We've tested hundreds of runners to design the crash pad under your heel that creates a cushioned, smooth transition from heel to toe. These findings have also created an airy upper with breathability right where you need it. Cushioned responsiveness A Zoom Air unit in the forefoot provides responsive cushioning. Every step helps generate energy return to move you forward. It combines with a foam midsole for a firm but smooth and stable feel when your foot hits the ground. Backed by data from hundreds of runners helped inform the placement of the crash pad on the heel. It provides extra cushioning for heel-to-toe transitions and supports runners who tend to overpronate. This information has also been used to place the cooling exactly where you need it. FLEXIBLE AND STURDY The durable rubber sole is built for mileage. Grooves in the forefoot for flexibility and vertical grooves on the side provide stability. Mesh is designed for durability. Laces for a secure feeling. A softer and more durable lining around the heel and ankle prevents socks from bunching up while running. Cushy tongue provides helps pad the laces. Molded heel securely hugs your foot.