2013 has been a stellar year for athletic apparel giant Nike ( NKE). The $68 billion stock has rallied more than 47% since the calendar flipped over to January, besting the broad market by a factor of two. And while it's hard to call Nike cheap at current prices, Nike's big long-term growth opportunities justify the premium. >>3 Big Stocks on Traders' Radars Nike owns one of the most valuable brands in the world, a fact that guarantees premium pricing for the firm's huge array of footwear and clothes. With football season now well underway, investors should start seeing the benefits of the five-year apparel contract Nike penned with the NFL -- but that's not the big growth story in this stock. For that, you have to travel a bit further. Specifically, Nike's growth is taking place in emerging markets like China, India, and Latin America, where burgeoning middle-class populations are increasing demand for "attainable status symbols" (such as a pair of trainers with a big swoosh on the side). Size comes with some big advantages, and Nike's pricing power over its retailers is the biggest one. Because athleticwear retailers rely on Nike to stock their shelves, the firm is still able to command higher price tags for its products, and retailers will take lower margins in exchange for consistent inventory turnover. A fortress balance sheet with a solid net cash position rounds out the picture in this apparel giant.