Foot Locker (FL) reported Friday a better-than-expected 36% increase in first-quarter profit and improved margins on sharply higher sales at its more established stores.

The upbeat results mark its ninth consecutive of year-over-year sales and earnings growth, a reflection of strong demand for powerhouse sports brands Nike (NKE) and Under Armour (UA).

The company reported net income that handily topped Wall Street estimates of $128 million, or 83 cents a share, compared with a year-earlier $94 million, or 60 cents.

Revenue for the three months ended April 28 was up 8.7% to $1.58 billion from $1.45 billion a year ago, led by a 9.7% increase in comparable sales, a key growth metric for retailers.

Analysts in a Thomson Reuters poll were looking for earnings of just 74 cents a share on sales of $1.55 billion.

“2012 has gotten off to an outstanding start, with our first quarter results representing the highest level of quarterly earnings in the company's history as an athletic business," Foot Locker CEO Ken Hicks said in a statement.

The company repurchased $27 million worth of shares under its $400 million share repurchase program in its latest quarter. 

Foot Locker's finance head, Lauren Peters, said the strong financial position enables the company to increases investments in what it believes are high-return growth opportunities.

The company’s smaller rival, Hibbett Sports (HIBB) also reported a stronger first-quarter profit on a double-digit jump in same-store sales.

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