Under Armour Velociti 4 Running Shoes There's fast, then there's Under Armour FLOW fast. Lightweight, rubberless, and durable, Under Armour's newest cushioning, gives a close-to-the-ground, grippy feeling of speed. The kind of speed that feels like you've got the wind at your back. Flat Synthetic Upper Featuring a comfortable flat upper, the Velociti 4 from Under Armour had been designed to deliver zonal dynamic stretch, containment and breathability where you need it.