Hard Surfaces
We often read or hear that human feet are not equipped to cope with hard surfaces. Our experience, current medical research and a small amount of thought on the long history of mankind indicates this is just not so. Some podiatrists and all shoe companies will paint a picture of soft fragile feet being pounded mercilessly on unforgiving surfaces. However, the fact of the matter is that the human animal adapts to these conditions with toughening and (more importantly) a graceful (non-pounding) style of walking and running. In "Running-related injury prevention through barefoot adaptations," Steven E. Robbins and Adel M. Hanna wrote:

A number of reports indicate an extremely low running-related injury frequency in barefoot populations in contrast to reports about shod populations ...

The opinion that the lower extremities are inherently fragile goes against the authors' understanding of the concept of natural selection .....

A paradox in presented of lower extremity fragility associated with the wearing of protective footwear and relative resistance to injury in the barefoot or unprotected state. To explain this paradox, the authors hypothesized that there exist adaptations associated with barefoot activity that provide impact absorption and protection against running-related injuries. An adaptation involving foot arch deflection on loading is hypothesized to be an important adaptation providing impact absorption. In contrast, it is hypothesized that the known rigidity of the shod foot may explain the reported high injury frequency in North American runners [click here for the full extract].

What these researchers are saying (see also this and other articles), is that when we have the sensory feedback from our bare feet, we modify our landing style to moderate impact (biofeedback), putting less stress on our feet, ankles and knees than if our feet had been desensitized (or fooled) by padded shoes.

In "Survey in China and India of Feet That Have Never Worn Shoes," by Samuel B. Shulman, we have the following:

... One hundred and eighteen of those interviewed were rickshaw coolies. Because these men spend very long hours each day on cobblestone or other hard roads pulling their passengers at a run it was of particular interest to survey them. If anything, their feet were more perfect than the others. All of them, however, gave a history of much pain and swelling of the foot and ankle during the first few days of work as a rickshaw puller. But after either a rest of two days or a week's more work on their feet, the pain and swelling passed away and never returned again. There is no occupation more strenuous for the feet than trotting a rickshaw on hard pavement for many hours each day yet these men do it without pain or pathology. [click here for the full extract].

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