Under Armour Micro G Assert IV Trainers All-black running trainers from Under Armour with silver highlights. The Mico G Assert IV features a slimmer athletic cut that delivers better mobility by eliminating the bulk of extra fabric. Formfitting, breathable mesh delivers ultra lightweight performance. The full-length 4D Foam. sock liner conforms to your foot's exact shape, eliminating slippage. Full-length Micro G. Foam turns cushioned landings into explosive take-offs. In addition, the solid rubber outsole is strategically placed on high wear areas for full ground contact and traction, with less weight.