Running Into Motherhood: How an Expectant Athlete Ran a 5:26 Mile Just Days Before Giving Birth

At 38 weeks pregnant and just days away from her due date, Kylie Mantz stepped onto the running track at Brigham Young University in Provo, Utah. While most expectant mothers in their final month of pregnancy are resting at home, the 24-year-old athlete pinned bib number 38 to her shirt—a symbolic gesture representing each week of her pregnancy—and prepared to run a full mile.

Supported by a group of female runners who took turns pacing her, Kylie launched into her run with a blazing 77-second opening lap. Despite running at an altitude of over 4,600 feet above sea level, she crossed the finish line in a remarkable 5 minutes and 26.2 seconds. Her husband, Conner Mantz, holds the American marathon record and is one of the fastest runners in the nation, but on that afternoon, the spotlight belonged entirely to Kylie.

This incredible track performance marked the finale of a unique chapter that started months earlier. In November 2025, Kylie won her very first marathon in Fresno, California, with a time of 2 hours, 43 minutes, and 49 seconds. It was only weeks after crossing that finish line that she discovered she was already pregnant during the race. As Kylie put it, they started the pregnancy with a marathon and decided to end it with a fast mile.

Just ten days after her viral track run, Kylie and Conner welcomed their first child, a healthy baby boy named William. While medical experts emphasize that high-intensity running at 38 weeks is only suitable for elite, highly trained athletes with uncomplicated pregnancies, Kylie’s journey stands as an inspiring testament to human determination, athletic endurance, and trust in one’s body.