Kylie Mantz Ran a Blazing Fast Marathon Debut. She Didn’t Realize She Was Pregnant
Runner's World
February 14, 2026
AI-Generated Deep Dive Summary
Kylie Mantz made headlines after running an impressive debut marathon, finishing in 2:43:49—a time close enough to the U.S. Olympic Marathon Trials qualifying mark that she didn’t realize she was pregnant during the race. The discovery came weeks later, adding a touching twist to her story. Married to Olympian Conner Mantz, Kylie had always dreamed of starting a family but chose to pursue running as a way to connect with her husband and build their future together.
Kylie and Conner met at Brigham Young University (BYU) in 2019. After an 18-month mission trip, she encouraged him to move on, but they stayed together, eventually tying the knot six days after Conner’s first professional marathon in Chicago in 2022. By then, their focus had shifted from building a family to pursuing running careers. Kylie, an elementary education major, joined BYU’s track team and showed remarkable talent, clocking a 17:49 time in the 5,000 meters. She even walked onto the women's NCAA team, a prestigious achievement.
Though her marathon debut didn’t go as planned—she fell short of her goal pace—the experience was still historic. Kylie’s journey reflects both athletic dedication and personal resilience. As she balanced training with the emotional highs and lows of trying to conceive, running served as an outlet for stress and a way to stay grounded. Her story is a testament to perseverance, proving that even when life takes unexpected turns, one can still achieve greatness.
For fitness enthusiasts, Kylie’s tale is inspiring on multiple levels. It highlights the importance of determination and hard work in achieving personal goals, whether they’re athletic or related to
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Originally published on Runner's World on 2/14/2026