South Korean running influencer Yoo Ji-won, a 25-year-old graduate student at the Korea Advanced Institute of Science and Technology (KAIST), has died after collapsing near the finish of the 2026 Seoul Race half marathon on Sunday, October 11. The cause of death has not been publicly disclosed.
What Happened at the Seoul Race
Yoo lost consciousness at approximately the 20.6-kilometer mark of the 21.1-kilometer course, around 8:49 a.m. — roughly 500 meters, or less than half a mile, from the finish line. On-site medical staff provided immediate first aid, including CPR, before she was taken by ambulance to a nearby hospital, where she died later that day.
The race’s organizing committee confirmed the death the following day in an Instagram statement. “We would also like to offer our condolences to the participants, whose hearts must be heavy upon hearing the tragic news of the deceased,” the committee wrote. “The organizing committee will closely examine the relevant matters and take necessary follow-up measures.”
According to Resonate Voices, a European outlet covering East and Southeast Asian news, authorities have not determined a cause of death.
A Friend’s Tribute
Yoo was identified publicly by her friend and fellow running content creator Bummy, who shared an emotional Instagram post recalling the moments after the race.
“Near the finish line of the Seoul Race, I saw a crowd gathering and thought someone must have been hurt,” Bummy wrote in Korean. “As soon as I crossed the finish line, I looked for you on the awards podium, but then came the unsettling news, and I began to sense a reality I didn’t want to believe. I dropped everything and rushed to the hospital, hoping to see you one last time, but I am so sorry I couldn’t stay by your side until the very end.”
Who Was Yoo Ji-won?
Born in 2001, Yoo was a graduate student at KAIST, where she researched artificial intelligence semiconductors. Alongside her academic work, she was an active amateur runner who shared her training, race results and passion for the sport with more than 8,000 followers on Instagram.
She had achieved notable results as an amateur, including completing the full Seoul Marathon in 2:56:32 in March 2026 and winning the women’s masters 10K category at the Gunsan Saemangeum Marathon in April. Her last Instagram update came on October 4, when she posted her time from a recent 10-kilometer run.
Tributes from fellow runners and followers have continued to fill the comments on her account.
What’s Next
The race organizing committee has said it will examine the circumstances and take follow-up measures. No official cause of death has been announced.
