Some upstream here were questioning whether trackhead should be preaching the minimalist gospel when he doesn't have a PhD in shoes.
Michael Yessis has a PhD and is a well known biomechanics expert. He has written several books on the subject. One is titled Explosive Running. In the chapter titled Barefoot Running, he goes into some detail about why training shoes too often injure people. A sampling:
"Once the natural foot structures are weakened, it becomes necessary to rely on external support structures (such as running shoes) to take over the normal functions of the foot. But the support given by various shoes does not match that given by a well functioning foot, nor is the support functional."
"Some running-shoe studies indicate that running shoes are the cause of many running injuries. This makes sense for two important reasons: (1) the shoes allow you to run incorrectly incorrectly by landing on the heel, wich creates high braking forces, and (2) the shoes do not allow the support structures to function as needed in the running stride."
"I recently worked with a young female runner who had severe ankle and knee problems. After videotaping her, I saw no major discrepancies in technique that could be causing the problem. I then videotaped the foot action very carefully. When she ran wearing running shoes it was possible to see foot overpronation very clearly. I then had her run barefoot, and to our surprise, there was no excessive pronation. The foot remained in perfect alignment with the shin during landing and takeoff. The overpronation was caused by the shoes, which in turn caused the ankle and knee problems. Once we changed the shoes, the problems were alleviated."
"A recent study by physical therapists Bruce Wilk and William Gutierrez found that 30 to 50 percent of new running shoes have defects that can lead to running problems . . . The study was published in the Winter 2000 issue of The American Medical Athletic Association Journal (vol. 14, no. 1).
"Some studies show that the more money runners spend on their shoes, the greater the number of injuries they incur!"
In my experience, you actually have to retrain yourself to run once you make the switch to minimalist shoes. You learn to run with a midfoot plant and a shorter, quicker stride and a that allows you to take maximum advantage of the potential energy stored in your elastic tissues. As a result, you waste very little energy on contracting your muscles, and there's very little vertical oscillation (i.e., your pelvis drops very little during the support phase of your stride). And it's just a lot more fun to run. I haven't actually seen Kim Smith run in person or even in video, but from the stills I've seen, it looks like she might be a good model of this sort of efficiency.
By the way, I highly recommend Yessis' book, and not just for the sections on running shoes. It provides a lot of valuable information on active stretching, injury prevention, and strength/power training.
Sorry about the long post.
