Shares of Under Armour Inc. jumped 3.5% in premarket trade Friday, after J.P. Morgan turned bullish on the athletic gear maker for the first time in at least three years, following an upbeat meeting with management. Analyst Matthew Boss raised his rating to overweight from neutral, and his stock price target to $29, which is 33% above Thursday's closing price of $21.88, from $23. Boss said the tone from the meeting was "controlled confidence" in the brand's direction, with earnings and revenue growth acceleration driven by the combination of the company's product, innovation and marketing strategy. That follows the company's "shrink phase" aimed at product rationalization, inventory reduction and vendor base consolidation. Boss said Under Armour is now positioned for "multi-year gross margin expansion." The stock has rallied 23.8% year to date through Thursday, while the SPDR Consumer Discretionary Select Sector ETF has climbed 18% and the S&P 500 has advanced 15%.