Adidas AG, the world's second largest sporting goods maker, has filed a case against Baltimore-based athletic apparel and shoe maker Under Armour Inc, claiming that the latter's exercise tracking and fitness monitoring products infringed on the patents it held, Bloomberg reported.

In a complaint lodged in a Wilmington, Delaware federal court, Adidas said it owned the patents that give technology for mobile applications products that monitor heart rates, number of calories burned and other data while a user is working out. The lawsuit alleged that Under Armour Inc's chest straps, watches and the software and mobile applications that support them that are being sold under its Armour39 brand were an infringement of its patents. Adidas also said that the mobile products that are being offered by the MapMyFitness unit of Under Armour violated the patents it held, Bloomberg reported.

The complaint comes as rivalry heats up among companies specializing in sports wear as they provide an online way for health buffs to track their training and performance. Last year, MapMyFitness, which boasts of 20 million users around the world, was bought by Under Armour in a deal worth around $150 million, the report said.

The complaint said that the director of research for Under Armour worked as a senior engineering manager at Adidas which holds headquarters in Herzogenaurach, Germany. Adidas said in the complaint, "Accordingly, Under Armour, by and through its director of innovation and research, has direct knowledge of Adidas' patent portfolio."

Adidas listed infringement claims of 10 patents and is asking the court to stop the conduct and award it reasonable royalty. It is also seeking triple damages for what it claims as willful infringement, the report said.

The media relations office of Under Armour still has to give a comment to the lawsuit after it was asked through email, Bloomberg reported.