I'm sure we've all heard about people who train barefoot. A lot of us have looked at them like they're crazy. Shoes give added support, cushioning, and protection to the foot, right?
Well, is it right? First lets look at some anecdotal evidence:
Shoes are a fairly recent invention, being only several thousands of years old. The Hominini tribe, the earliest ancestors of Homo-sapiens genus, divulged from their Pan genus brethren 6.3 million years ago. The human foot, and all the body's supporting mechanisms for the foot, evolved over millions of years to be fairly good at what it does. We could probably trace the evolution of the human foot even farther back, but lets go from there. Human feet were designed to be walked on. Shoes stop you from walking on them.
You are probably wearing shoes right now. Take them off, and put one on your desk. Look at it. Do you see how the toe is curved upward? This is done so it is even possible to walk in shoes.
When you walk barefoot, you strike with the middle of the heel, rolling forward onto the balls of the feet, and then there is a powerful push-off from the balls of the feet. When running, they were designed to strike in the midfoot, not the heel. Shoes alter your gait - when you walk in shoes, the back of your heel strikes first, and your foot rolls forward, and then you push off your toes which creates a rocking motion. When you run with shoes, it feels "natural" to run heel-to-toe, which causes a jarring shock to your ankles and knees. High heels exacerbate problems caused by an unnatural position of the foot. They cause different and unnatural stresses on the bones of the foot, the ankle, the knee, up to the pelvis and even through the shoulders. It raises the heel, which is the foot's natural supporter of weight, by an inch, two inches, sometimes even four or five inches! The entire weight of the body is transferred to the ball of the foot, while the pelvis and the shoulders tilt to compensate for the difference in weight distribution.