Under Armour Speedform Fortis Twist Running Shoes ArmourVent Upper - Improves breathability and ventilation. Moisture Management - Wicks away excess sweat and moisture. Breathable - Encourages cool air to circulate. Stretchy Jacquard Knit Fabric - Helps to deliver a full range of motion. 4D Foam - Embedded within the sockliner for added cushioning and comfort.