“Elle would always finish first or second, and I’d be near the back,” said Jamie St. Pierre, who studied dairy management at Cornell before returning to Vermont to help run his family’s farm. “You had to get your cow all polished up and get the hair clipped perfectly, and that wasn’t my cup of tea.”

Purrier St. Pierre was reminded of competing at the fair when she was doing some work in the barn not too long ago, and she caught a whiff of fresh sawdust. There was always fresh sawdust at the fair, and back then, the scent would trigger something inside her — a mix of nerves and excitement, along with a desire to win. She gets the same feeling now whenever she approaches the start of a race.

It was not until she was a freshman at Richford High School that her innate talent revealed itself. She went out for girls’ basketball and dominated a preseason time trial in the mile. She later joined the track team, then ran cross-country the following fall. It turned out that she was a natural, even if she was not enamored with the general concept of running long distances.

“I didn’t like it at all,” she said. “I liked that I was good at it, but I didn’t understand it. It was just something that I was doing.”

Richard Flint, one of Purrier St. Pierre’s high school coaches, saw her potential. He would trail her in his truck on runs, which drew the attention of the Border Patrol on at least one occasion. “When they pulled him over, he told me to keep running,” Purrier St. Pierre said.

She began to take the sport more seriously, she said, when she realized that she could earn a college scholarship. But even as she asserted her dominance, winning state title after state title, her training never exceeded 30 miles a week, she said — a relatively light total, even for someone her age.

At New Hampshire, she continued to be measured with her approach, gradually building her weekly mileage from 40 as a freshman to 50 as a sophomore. In the process, she said, she largely avoided injuries and never experienced the sort of burnout that has caused problems for other runners. She also discovered the joy of running, drawing on the camaraderie she felt among her teammates.