At 55 years old, Heidi Christensen relishes the chance to defy stereotypes. “You didn’t just get passed by an old person,” she says of the 20- and 30-somethings she zooms by on bike paths. “You got passed by an old lady.”
Almost three decades ago, chances didn’t look good that she’d be passing anyone while bicycling—or running or swimming—ever again. This, despite the fact that she was a professional triathlete who, at age 28, had just come in fifth at the Ironman World Championships.