This running club is pounding the pavement without sneakers.
"I've been running barefoot for about 2.5 years now," says Brian Hurtado.
Arielle Lublin adds, "I felt free-er and was actually faster than running in my shoes."
Many people are getting into barefoot running, convinced it's better for their body. Joe Maller says he had knee, hip and back problems before going barefoot. "I'm running much more than I was before and painlessly and a little faster."
Many barefoot runners wear a special running shoe - which doesn't offer any support - but protects your skin from hitting the ground.
Yet there's no evidence going barefoot is a healthier choice. Doctors say the trend is causing injuries especially for runners just getting started.
Barefoot runners use different muscles. Doctors say their strike tends to be shorter and they land on another part of their foot and that could land some people in the doctor's office.
"Stress fractures, because the bones that lead to the toes are getting too much strain//patients that come in with tenditinitis, both of the arch and the achilles and major symptoms seem to be overuse type injuries or lack of support type injuries," says Dr. Bob Baravarian of UCLA Medical Center.
Chris Hawson has been running barefoot for two years. His advice - don't rush into it .
"You really do have to ease back certaintly in distance and in pace and frequency while your body adjusts."
It could take months to make the transition out of your sneakers and experts warn you should stop immediately if you have bone or joint pain.