The demand for athletic apparel has risen sharply in recent years, as new players among apparel- and shoemakers have forced established giants to up their game. Nike ( NKE 0.07% ) continues to dominate the athletic footwear industry, but Under Armour ( UAA -0.65% ) has challenged the company on the apparel side of the business and more recently has gone heads-up against Nike with its own shoes. That buzz has helped increase awareness of athletic specialty products generally.