Yoo Ji-won dies after collapsing during Seoul Race half-marathon

Yoo Ji-won, a 25-year-old running influencer and KAIST graduate student researching AI semiconductors, passed away after collapsing during the 2026 Seoul Race half-marathon. The incident occurred on October 11 at approximately 8:49 AM near the 20.6 km mark, roughly 500 meters from the finish line.

Emergency responders administered on-site first aid and CPR before transporting her to a medical facility via ambulance, but she could not be revived. The Seoul Race Organizing Committee issued a formal statement expressing condolences to the family and announced that they would conduct a thorough investigation into the incident.

While an official cause of death has not been confirmed, medical experts note that sudden cardiac death in athletes under 35 is often linked to underlying structural heart issues, such as hypertrophic cardiomyopathy. The news has prompted widespread mourning across the South Korean running and academic communities.