NordicTrack maker iFit Health & Fitness Inc. filed a U.S. trade complaint seeking to block imports of Peloton Interactive Inc.’s stationary bikes, escalating a dispute over home-fitness equipment and adding to Peloton’s woes.

While the case involves the Peloton Bike+ stationary bikes that alternate between bicycling and weight lifting, “the unauthorized use of patented inventions by Peloton is pervasive,” iFit said in the complaint filed Wednesday with the U.S. International Trade Commission.

Peloton has had a rough start to 2022. Its stock has plunged more than 80% from its pandemic-fueled high a year ago amid concerns of slowing sales; an activist investor is calling for a sale of the company and the ouster of John Foley, Peloton’s co-founder and chief executive officer; and a former sales representative accused the company of forcing employees to work without paying overtime.

Peloton and iFit are already embroiled in a hotly-fought battle over patents in federal court, but the trade agency works more quickly than district courts and has the power to halt products from crossing the U.S. border.

The newest case involves stationary bikes that have free weight cradles and a patent issued to iFit in May. The invention is used in the NordicTrack S15i Studio Bike, NordicTrack S22i Studio Cycle, Pro-Form Studio Bike Pro, and Pro-Form Studio Bike Pro 22, according to the complaint.

Also named in the complaint are Peloton’s Taiwan-based manufacturers—Tonic Fitness, which Peloton bought in 2019, and Rexon Industrial Corp.

Jessica Kleiman, a Peloton spokesperson, said the company doesn’t comment on pending litigation.

The Washington agency is a favored forum for companies looking to inflict the ultimate pain on a rival or to pressure companies into paying royalties. Dish Network Corp. and its Sling TV have accused Peloton, iFit and Mirror owner Lululemon Athletica Inc. of infringing patents for streaming video over the internet, with a trial at the ITC scheduled to begin next month.

The home-fitness market saw rapid growth amid the pandemic, leading to the inevitable legal battles as companies sought to use their patents to slow down rivals and each accusing the other of copying patented inventions. There was even a legal fight over Peloton’s use of the name Bike+.

The case is In the Matter of Certain Electronic Exercise Systems, 337-3602, U.S. International Trade Commission (Washington).