Europe's biggest maker of sporting products, Adidas, said Tuesday that profits dropped in the first quarter mainly due to increased costs related to its US subsidiary Reebok.

"The Reebok integration is beginning to pay off as we realize the first revenue and cost synergies," chief executive Herbert Hainer said in a statement outlining the latest results. "Adidas and TaylorMade-Adidas Golf impressed with strong product launches."

This report met with the expectations of analysts, following a warning earlier this year from  Hainer that results for the January-April period would fall more than 10 percent.

The German-based company said profit before interest and tax (EBIT) was down 8 percent from a year ago to €229 million ($309 million), while net earnings dropped 11 percent to €128 million.

However, investors reacted positive to the news, with Adidas shares on the Frankfurt Stock Exchange up 4.4 percent to €44.14. Adidas said sales rose 3 percent to 2.54 billion euros in the first quarter as it integrated the operations of Reebok, which it purchased in 2006 for 3.8 billion dollars.

Adidas released its results a day after its cross-town rival Puma reported a 3.7 increase in first-quarter profit to 96.6 million euros, but lowered its growth target for the rest of the year.