Under Armour puts performance first. The American activewear brand uses breathable and quick-drying fabrics that power through the toughest workouts. Find new and used clothing featuring innovative cooling or insulating technologies. Supportive fits and simple primary colors make up the label's signature style. Versatile matching sets transition easily from the gym to the street. Look for secondhand Under Armour gear that's suitable for athletes and home fitness fans alike. Power up your workouts with the brand's innovative designs.