[2] At only ten years old, while running with her parents, Patrick and Denise, Tuohy was spotted as a potentially remarkable talent by her coach-to-be, Brian Diglio.

In the 2017 Cross Country season during the Manhattan College XC Invite, in the Bronx, New York, she took 32 seconds off the historic Van Cortlandt Park course record with a time of 13:21 for the 2.5 mile / 4 kilometer event.

She then later won the Nike National cross country (NXN) championship on December 2, 2017, as a sophomore with a 5K time of 16:44.7 to cap an undefeated season.

[6] On September 22, at the Ocean State Invitational, Tuohy ran the fastest American girls cross country 5K ever with a time of 16:06.87, lowering the course record by 88 s.[7] Her time clipped almost 17 s from Katie Rainsberger's 2016 best-ever high school girls' standard on any course, running faster than all but one of over 1000 high school boys running the sandy course that day.

[9] On December 1, despite her missing her state section championship race with knee tendonitis, a few weeks earlier,[10] she repeated as Nike's Cross Nationals Individual Champion.

[12] Her high school coach, Brian Diglio, who was also her Advanced Placement U.S. History teacher, endeavored to keep Tuohy in check while guarding her progress.

It was thought that experiencing stiffer competition from professional runners might be expected to benefit her regarding the possibility of Olympic Trials training to follow in 2020.

[31] Two weeks after soundly beating 2020 NCAA XC Champ Mercy Chelangat at Notre Dame, Tuohy won Wisconsin's Nuttycombe 6K cross country invitational in 19:44.3, leading her NC State team to a tiebreaker win over the second ranked University of New Mexico Lobos.

[35] Tuohy opened the 2023 season on January 28 by breaking the NCAA indoor mile record, finishing third to two professionals, in 4:24.26 at the Dr. Sander Invitational Columbia Challenge.

[36] On February 11 at the Millrose Games in New York, she set a new NCAA indoor 3000 m record with a time of 8:35.20, to break Karissa Schweizer's previous collegiate best of 8:41.60.

[37] In Tuohy’s first race of the 2023 Cross country season, she finished second to Florida’s Parker Valby at the Nuttycombe Invitational.

On December 6, 2023, Tuohy announced that she had signed a professional contract with Adidas and would forgo her final track season at NC State.

[44] After winning the Nike Girls Cross Country Championships in Portland, Oregon, in 2019, she was again named the Gatorade Player of the Year, matching track star and future Olympian, Marion Jones as the only other such three-peat winner.