Simpson was briefly without a pulse before bystanders and emergency responders intervened. Emergency medical services arrived quickly, restored her pulse and rushed her to a hospital.
The 39-year-old Simpson was taking part in a community track event hosted by Sir Walter Running, with runners of all levels encouraged to attend. The event featured a chance to meet Simpson.
Simpson, a three-time Olympian and bronze medalist who is widely considered the most accomplished U.S. women's 1,500-meter runner, had been making appearances at running events in the Triangle after becoming chief running officer for Fleet Feet, a Carrboro-based company.
"We are incredibly grateful to the individuals who responded immediately, as well as EMS and the medical professionals who handled the situation with such care, urgency, and professionalism," the "Sir Walter Running Team" wrote on Instagram on Wednesday.
The incident occurred during the Sir Walter Miler, a pop-up event held every Tuesday in June at Williams Stadium at Athens Drive High School that draws runners of all ages to test their fastest mile times. Simpson attended Tuesday's event, cheering on participants and pacing one of the mile groups.
The statement added that "Jenny is receiving excellent medical care, and our thoughts are with her and her family during this time."
Simpson's current health status remains unclear. The organization asked for prayers for Simpson and her family as they hope for the best.
Local running coach Jess Hofheimer, who met Simpson at a small business event Saturday, said she made an immediate impression.
"I said oh my gosh, that's Jenny Simpson. She has made such a huge impact on our sport," Hofheimer said. "And she just, like, jumped right in. It was like we were old friends."
At the event, Simpson was seen encouraging runners, from beginners to older participants, something community members said reflected her love for the sport.
"It's so cool because you know what she's experienced and achieved, and I do think it gives her just as much joy to watch a newbie runner or someone 60 or 70 as it did when she was an Olympian," Hofheimer said.
In the aftermath of the medical episode, members of the local running community expressed concern and support.
"Yeah. I mean, look, like right now I feel like, you know, from the very moment that we realized that she was in distress, like everyone is just coming together to send love and prayers and healing energy, her way to to her to her family," Hofheimer said.
Community members said they plan to support Simpson as she recovers.
"And we are just so grateful for how she has shown up for this for this community and that we are like an army of love and people who are ready to return, not to her in every and any way that that we can now and on the road ahead," Hoffheimer said.
Simpson won the bronze medal in the 1,500 meters at the 2016 Rio de Janeiro Games. She also won the 1,500 at the 2011 world championships, along with silver medals in 2013 and 2017.
- The Associated Press contributed.
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