At least 19 runners have received hospital treatment after experiencing "unusual symptoms" following the Santa Barbara Half Marathon in California.
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The event took place on Sunday, November 8, with approximately 7,500 competitors participating in the 13.1-mile race.
Running brand Hoka sponsored the half marathon, which Run Local organized.
19 Runners Hospitalized With Unusual Symptoms Following Half Marathon
The 19 participants received medical attention at Santa Barbara Cottage Hospital and Goleta Valley Cottage Hospital after the event.
"We have a larger than expected number of emergency visits that are tracked to participants in this morning's organized run in [Santa Barbara]," said Cottage Health in a statement.
"This morning 19 participants arrived at Cottage [emergency departments], a number of them with similar symptoms of undetermined cause. We are working to determine whether this is due to the heat or other factors."
Race director David Monico later revealed that 15 of those hospitalized had suffered from "heat exhaustion". He added that none had sustained serious injuries.
"I hate to use the word normal, because if we get one transport we don't like it, but for a lot of these endurance events you get transports, especially on these warmer days," he said.
Authorities Investigate Unusual Symptoms at Santa Barbara Half Marathon
According to local reports, organizers positioned water stations approximately every 1.5 to 2.5 miles along the race route.
The stations provided Voli Hydration Sunset Strawberry Lemonade, water and energy gels. While runners could also access assorted snacks at the finish line.
Authorities have launched an investigation following the unusually high number of participants "seeking medical treatment for unusual symptoms after the event concluded."
Those affected arrived at medical facilities by ambulance, private transportation or as walk-in patients.
"The cause of the reported symptoms has not been confirmed," police said. "There is no specific action recommended for the public at this time; however, participants who feel unwell should seek medical attention and follow guidance from healthcare professionals."
Investigators have urged anyone with information about the incident, or anyone who experienced unusual symptoms following the race, to contact Sgt. Andre Miller at 805-897-2330.
