They're supporting El Segundo firefighter Jose Zambrano, who is nicknamed "Fireman Joe", in the 24-hour treadmill challenge.
This is his latest effort to raise money for St. Jude Children's Research Hospital.
Proceeds will help in the fight against childhood cancer.
He's been taking on these challenges for a few years now, after a friend lost his daughter to cancer.
The fundraiser ran through 6 p.m. Sunday at the UFC Gym in Corona.
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