The following Mark's Daily Apple article was written by Mark Sisson and is narrated by Tina

Lehman.

Why what you walk or run on matters.

I've always preferred traversing natural surfaces.

Growing up in New England, I developed my cross-country running chops actually running across the country surrounding my house.

My favorite endurance events were those involving trees and trails to the point that I might still be doing them if they

were exclusively nature-based. Even today, I cherish my hikes through the Malibu Hills and rather

begrudgingly go for neighborhood walks only because the sidewalk is so convenient. Walking on flat,

linear, man-made surfaces is certainly fine, especially if I've got my wife or dog or friend,

or I'm exploring a new city.

But naturally deposited ground full of dips and peaks and studded with random deformation is ideal.

And there's growing evidence that it's better for you too.

I'll ignore the grounding slash earthing issue for now. I've covered grounding before, and it's

difficult, maybe impossible, to disentangle the proposed effects of electron transfer from the known

effects of walking barefoot through natural settings. I'll also ignore the footwear,

even though it certainly matters. You guys know that, so I'll assume we're all

in minimalist-type shoes or none at all. Thick-soled shoes dampen the experience and benefits

of traversing natural terrain. If you're wearing hiking boots, walking surfaces don't matter much.

Your feet are too sedentary to notice a difference. So let's just get straight to it.

Our hunter-gatherer ancestors walked exclusively across natural uneven surfaces. Sometimes it was hard,

hard stone carved by glaciers. Sometimes it was soft, sand or loamy earth. Sometimes it was firm

but forgiving, such as jungle floors and dirt trails.

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