AI chip researcher dies after collapsing 500 meters from Seoul half-marathon finish

A South Korean graduate student researching AI chips collapsed about 500 meters from the finish of the Seoul Race half-marathon in central Seoul and later died.

She collapsed at the 20.6-kilometer mark of the 21-kilometer course on Oct. 11, the race's organizing committee said in a notice on its website on Oct. 12.

A race official who found her near Gwancheol-dong in Jongno District called emergency services and performed CPR, according to the Seoul Metropolitan Government, which hosts the race. She did not regain consciousness and died after being taken to a nearby hospital.

The committee's notice, which did not name the runner, offered condolences to her family and said the committee would closely review the matter and take necessary follow-up measures. No cause of death has been made public.

Running influencer

The runner was Yoo Ji-won, a graduate student at the Korea Advanced Institute of Science and Technology (KAIST) born in 2001, Newspim reported. She researched AI semiconductors and was active as a running influencer, sharing her training and race results on social media.

She finished the Seoul Marathon on March 15 in 2:56:32 and won the women's masters 10-kilometer race at the Gunsan Saemangeum Marathon on April 5, the outlet said. Friends and fellow runners have since left tributes online.

Yoo said in a March interview on a running YouTube channel that she took up running in 2022 and began chasing faster times in the summer of 2025, Munhwa Ilbo reported. She described arriving at her lab at 9 a.m. and running for about two hours from 8 p.m., then returning to the lab on days when work remained.

About 12,000 runners entered this year’s Seoul Race, co-hosted by the daily Dong-A Ilbo. It started at Seoul Plaza at 7:30 a.m. with half-marathon and 11-kilometer courses.