Under Armour stock may have soared on quarterly results Thursday, but one Wall Street analyst is telling investors to avoid it.

Corinna Freedman, senior research analyst at BB&T Capital Markets, expects the bullishness surrounding the stock to be short lived.

"Short interest has been through the roof recently. There was a lot of negative market news. Obviously, people had concerns about the weather," said Freedman on CNBC's "Halftime Report." "They didn't raise guidance. Inventories are up 46 percent."

The nation's No. 2 sportswear maker reported its revenue jumped by 31 percent in its fourth quarter. Under Armour's apparel sales rose by more than 22 percent and its footwear sales nearly doubled.

Back in October, after the stock hit a 52-week high, Freedman downgraded it to "hold" from "buy," and she's standing by her position despite the blowout numbers in this latest quarter. Ahead of this upward move, Under Armour shares had been down about 30 percent over the past three months.

"When you dig down into the income statement and we start looking at the structural changes going on in growth margin — adding more expenses — the earnings power of this company diminishes a little bit," added Freedman. "This brand still has a very significant runway ahead of itself."

Under Armour's rivals, particularly Nike and Lululemon, may be the best plays for investors right now, according to trader and optionMonster.com co-founder Pete Najarian.

"Those two both, to me, still have incredible growth stories behind them and obviously with Lulu you have a margin expansion that they were just talking about," said Najarian. "If we get any kind of a pullback in Under Armour stock, that would be an opportunity. But I don't think you want to chase it."

Correction: An earlier version of this article misidentified Freedman's firm.