Here's what sold me on the whole barefoot-is-best notion. Try it at home:
1) Run in your running shoes, either on the road or on a treadmill.
Odds are if you're like most runners you have a heel strike and land heel-toe-heel-toe. It looks nice, it feels nice, and it's what we've been told is the correct way to run.
2) Now take your shoes (and maybe socks) off and repeat.
Yeah, how's that heel strike feel now? It probably hurts like crap. So after a few strides of shooting pain you've probably switched to a mid-foot or fore-foot strike to save your poor heels.
3) Put your shoes back on and repeat. Try to maintain the mid/fore-foot strike from step 2.
Difficult, no? Running shoes, with their soft, cushiony, and elevated heel, encourage a heel strike. But take the shoes away and that's not how our bodies are inclined to run. So why wear shoes that guide your feet to do something otherwise unnatural?
Here's an interresting visual that shows the force endured by the foot in a heel strike and a fore-foot strike. Note the high initial force of the heel strike as compared to the low initial force of the fore-foot strike. Imagine that force either shooting up the back of your leg or your body weight falling over the foot strike as the force is absorbed by your bent leg.
Part of the problem is shoe manufacturers make shoes that basically require a heel strike. Trying to fore-foot strike is traditional running shoes is about as comfortable as barefoot running with a heel strike. Either that or you feel like you're prancing. Take the ad below for example.
A heel strike with a big stride looks sexier, or so Nike wants you to think. But land on the fore-foot or the more comfortable mid-foot and all of that force is directly underneath your body instead of thrust out in front. If the purpose of running is to move forward with as little foot-ground contact as possible, then the fore-foot or mid-foot strike is the most efficient and natural way to land.
One of the first things I cover in my World History classes is human migration. We discuss the origin of Homo sapiens in East Africa and the eventual migration out of Africa, across Eurasia, south to Oceania, and finally across the Bering Land Bridge and south and eastward through the length of the Americas. They weren't walking thousands of miles in gel-cushioned stability shoes and I'm pretty sure they weren't heel-striking. Human evolution is a pretty incredible and we could help ourselves by not messing with it!