Lululemon said it saw strong sales this holiday season. (Lucas Jackson/Reuters)

Shares in Lululemon Athletica inc. rose sharply in after-hours trading Monday after the Vancouver-based activewear retail announced improved guidance for its fiscal fourth quarter.

The company said in a U.S. Securities and Exchange Commission filing issued after markets closed that it now anticipates net revenue for the quarter ending Jan. 31 will be in the range of $690 million to $695 million US, up from previous guidance of $670 million to $685 million US.

That would be an increase of about 15 per cent compared with the fourth quarter of fiscal 2014 or 19 per cent on a constant currency basis.

Diluted earnings per share are expected to be between 78 and 80 cents US for the quarter, up from previous guidance of 75 to 78 cents.

"We had a very successful holiday season driven by strong execution in stores and online during the key holiday weeks," CEO Laurent Potdevin said in a statement.

"Sales for the fourth quarter are exceeding expectations and gross margin rates and expenses remain in line with prior guidance."

On the Nasdaq, Lululemon shares closed up 82 cents or 1.52 per cent at $54.73 on Monday. However, in early after-hours trading, the stock surged $4.24 or 7.75 per cent to $58.97.