Last year, Maddie Hart won the Tahoe Rim Trail 100 Mile Run, making her the youngest person — male or female — to ever sweep the ultrarunning event. Ultrarunning, 50 km or longer, is starting to skew younger and faster. But traditionally the sport has been dominated by older, mostly malerunners who find extended success at enduring over long distances as the speed of their youth wanes. “I had low expectations, but I ran consistently,” she said. “I was running the whole time, and I was just super stoked with the win.”