Four years ago, Molly Seidel wasn’t just the next big thing. She was the top female distance runner in the NCAA with four national titles and the Olympic Trials on the horizon. But instead of signing a splashy contract with a shoe company, Seidel was sidelined with a sacral stress fracture and watched the U.S. Olympic Track Trials from the stands at Hayward Field, where her Notre Dame teammate Dani Aragon gave her a reality check. “You look like you’re dying,” Seidel remembers her friend saying. “You need to get help.” The truth was, the fastest woman in the NCAA...