Seventeen-year-old Alexa Efraimson ran a 16:08 at the Silicon Valley Turkey Trot 5K last month to place ninth overall. This week, it was officially ratified as a U.S. Junior girls record for the 5K road distance.

Efraimson’s time crushed a 12-year-old record set by current professional Molly Huddle, who ran a 16:23 at the Heritage Christian Home 5K in 2002 (Huddle was the overall winner of that race by more than 30 seconds). Efraimson could’ve flirted with breaking 16 minutes had she not stumbled and fallen just before the finish line of her race. Either way, she broke Huddle’s mark by a wide margin.

“Breaking the record actually surprised me,” Efraimson said. “I’ve met Molly Huddle and she’s just an incredible competitor and person. So I’m really honored to break the record of such a respected athlete.”

Huddle, now 30, owns the overall American record holder in the 5,000 meters on the track, which she set earlier this year with a time of 14:42.64.

Efraimson already has American high school records in the indoor 3,000 meters (9:00.16) and the 1,600 meters (4:33.29). She signed a contract with Nike earlier this year and will forgo her final year of high school eligibility and her college eligibility.