“I can’t sit still,” she said. “I want to ask my teachers if I can just stand in the corner.”

A typical workout for her is a 10-mile jog in 70 minutes, which she considers an easy tempo. She has personal bests of 16 minutes 51 seconds for five kilometers, 34:59 for 10 kilometers and 1:16:41 for the half-marathon.

Mark Hadley, who met his wife when they were cross-country runners at the University of Mississippi, said their daughter’s drive comes from within.

“It wasn’t planned this way,” he said. “With a kid, who knows if they’re going to want to run next week? Alana’s just never stopped.”

In October, Hadley was named USA Track & Field’s athlete of the week after she won an open cross-country meet in Charlotte that featured runners from college programs like Duke, Florida State and Davidson. She recalled that a few threw elbows in her direction at the start.

Not everyone is a fan of her precocious path. She heard from critics when she revealed that she was logging 55 miles a week at 13, and now that her workload has doubled, the chorus has grown louder: should a teenager be running so much, so soon?

No less an eminence than Bernard Lagat, the Olympic 1,500-meter medalist, voiced his concern during an exchange with Hadley on Twitter last year. Lagat, 38, who is an advocate of rest and moderation, pointed out that her mileage exceeded even his own.

Hadley’s approach, though unorthodox, is not without precedent. In 1984, Cathy O’Brien competed in the United States Olympic marathon trials at 16 and placed ninth, finishing in 2:34:24. O’Brien said she ran about 60 miles a week during training. By the time she qualified for the Olympics in 1988 and again in 1992, she was logging more than 100 miles a week.