From your first run to the finish line of that 10K the Solarboost 4 feels responsive mile after mile and day after day These adidas running shoes are built on fulllength BOOST with a control rail that guides the foot with each stride Throw in the Linear Energy Push system and you get a snappy ride that takes you from training to race dayLace closureTextile upperEVA control railBOOST midsoleWeight 108 ounces size 9Midsole drop 10 mm heel 32 mm forefoot 22 mmContinental Rubber outsoleUpper contains a minimum of 50 recycled content