From 5Ks To Full Marathons, The Gel-Kayano31 Shoe Is Designed For Adaptive Stability Features Which Keep You Feeling Supported When Your Legs Get Tired. Designed To Help You Experience A Softer And Smoother Stride During Your Training. Lightweight And Energetic Cushioning Materials Help Create Responsive Rebounds For A Faster Underfoot Feel. The Engineered Mesh Upper Is Designed To Help Provide Better Ventilation So That Your Feet Can Keep Cool And Comfortable While Running Longer Distances. The Asymmetrical Medial Design On The Upper Has Been Revamped To Help Create A More Supportive Fit For A More Comfortable Feel. By Updating The Outsole With An Asics grip Rubber Material, This Version Of The Gel-Kayan series Helps Provide Better Traction Throughout Your Run