Lamar Sepulveda hopes to have taken runners to new distances by the time he steps off his treadmill Saturday, July 14.

The 55-year-old Mar Vista resident will attempt to break the world record for most miles run on a treadmill in 12 hours, beginning at 8 a.m. in the 3600 block of Stewart Avenue.

Hoping to top the current record of 58.05 miles in half a day, the six-time Iron Man triathlete and ultra runner plans to raise funds and awareness for the Challenged Athletes Foundation. The nonprofit organization works to help people with physical disabilities pursue an active lifestyle through physical fitness and competitive athletics.

Sepulveda’s world record attempt will be streamed live at

Sepulveda is aiming to run a minimum of 58.1 miles or more on an SK treadmill provided by BH Fitness. Attendees will be encouraged to collectively challenge Sepulveda’s 12-hour distance mileage on a second treadmill.

Sepulveda is the founder of the “Pay It Forward” Challenge, which uses endurance sports to raise funds and awareness for charities and to inspire others to do so.

He is no stranger to extreme sports challenges. Sepulveda completed a 611-mile solo state-to-state swim-bike-run from Venice Beach to Phoenix, AZ in 2008, raising $15,000 for the Children’s Hospital of Orange County Cancer Institute where his son had been a leukemia patient.

All viewers (in-person and online) are encouraged to donate to the Challenged Athletes Foundation during this event. According to the foundation, many CAF-supported athletes will compete in the Paralympic Games this summer in London. ¤