It was once hyped as a worthy rival to Nike. But at present, Under Armour, founded by a 23-year-old former college athlete, is struggling to “just do it.” ...

Under Armour, the sports apparel company, said on Wednesday that its founder, Kevin Plank, would return as chief executive, in a leadership shake-up that will seek to revitalize the struggling brand.

Under Armour is debuting its first collection with Unless after acquiring the brand last summer. As part of the deal, Liedtke, a former Adidas exec who founded Unless in 2020, came on to work with ...