Kevin Plank, now former CEO of Under Armour, during a CNBC interview on Mad Money on Feb. 28th, 2018. Under Armour founder Kevin Plank will return as CEO more than four years after leaving the post, the athletic apparel retailer said Wednesday. Plank will take over effective April 1 and will succeed Stephanie Linnartz, who will stay on with the company as an advisor through the end of April. Plank, currently chair of the company's board, will remain a director but will hand over the chair position to Mohame ...