Shares of Under Armour (NYSE:UAA) are up nearly 70% so far this year, even despite a recent pullback on concerns for the athletic apparel specialist's growth in 2014.

Even so, the Fool's Steve Symington thinks shares of Under Armour are plenty attractive at today's levels. So attractive, in fact, that, as he explains in the video below, he'll soon double his personal position in Under Armour stock in the very near future. Keeping in mind that Under Armour currently represents around 4% of his personal portfolio, check out the video to get Steve's full take.

What do you think? Are shares of Under Armour worth buying today?