While some runners completely lose the shoes, others opt for minimal coverage. The oxymoron "barefoot running shoes" is like a glove for the feet designed to protect from glass and other hazards on the ground. Superlight minimalist shoes are a cross between barefoot shoes and traditional sneakers — there's little to no arch support and they're lower profile.
Greg Farris decided to try barefoot running to ease the pain on the outside of his knee, a problem commonly known as runner's knee. He was initially shoeless — running minutes at a time and gently building up. After three months, he switched to barefoot running shoes after developing calluses.
Halfway through a 5K run in January, he felt his right foot go numb, but he pushed on and finished the race. He saw a doctor and got a steroid shot, but the pain would not quit. He went to see another doctor, who took an X-ray and told him he had a stress fracture.
Farris was in a foot cast for three months. He recently started running again — in sneakers.
"I don't think my body is made to do it," he said, referring to barefoot running.
Experts say people can successfully lose the laces. The key is to break in slowly. Start by walking around barefoot. Run no more than a quarter mile to a mile every other day in the first week. Gradually increase the distance. Stop if bones or joints hurt. It can take months to make the change.
"Don't go helter skelter at the beginning," said Dr. Jeffrey Ross, an associate clinical professor of medicine at Baylor College of Medicine and chief of the Diabetic Foot Clinic at Ben Taub General Hospital in Houston.
A year and a half ago, Ross saw a steady stream — between three and six barefoot runners a week — with various aches and pain. It has since leveled off to about one a month.
Ross doesn't know why. It's possible that fewer people are trying it or those baring their feet are doing a better job adapting to the new running style.
There's one group foot experts say should avoid barefoot running: People with decreased sensation in their feet, a problem common among diabetics, since they won't be able to know when they get injured.
Harvard evolutionary biologist Daniel Lieberman runs a lab devoted to studying the effects of running form on injury rates. He thinks form matters more than footwear or lack of — don't overstride, have good posture and land gently.
In a 2010 study examining different running gaits, Lieberman and colleagues found that striking the ground heel first sends a shock up through the body while barefoot runners tend to have a more springy step. Even so, more research is needed into whether barefoot running helps avoid injury.
"The long and the short of it is that we know very little about how to help all runners — barefoot and shod — prevent getting injured. Barefoot running is no panacea. Shoes aren't either," said Lieberman, who runs barefoot except during the New England winters.
Carter, the ultramarathoner, blames himself for his injury. Before he shed his shoes, he never had a problem that kept him off his feet for two months.
In April, he ran his fourth 100-mile race — with shoes. Meanwhile, his pair of barefoot running shoes is collecting dust in the closet.
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