The struggling sportswear giant Under Armour confirmed on Sunday evening that it was assisting federal authorities conducting investigations into its accounting practices and related activities dating back to 2017.

“Under Armour is cooperating with the U.S. Securities and Exchange Commission and the U.S. Department of Justice investigations,” a spokesman for Under Armour said Sunday night. “The company began responding in July 2017 to requests for documents and information relating primarily to its accounting practices and related disclosures, and the company firmly believes that its accounting practices and disclosures were appropriate.”

The company was responding to reporting on Sunday from The Wall Street Journal, which said the authorities were looking into whether Under Armour had shifted sales from quarter to quarter to appear healthier.

Early Monday, Under Armour is scheduled to report its earnings for the third quarter.

The company built its reputation by making high-tech shoes and apparel for athletes. But its revenue has lagged in recent years behind rivals like Nike and Adidas, which were better positioned to take advantage of surging consumer demand for so-called athleisure wear.