Here are the key points from a study Dr. Daniel Lieberman did on Barefoot Running. This study was in the British science journal Nature magazine back in January 2010.
The article I draw from is on runbare.com entitled New Study by Dr. Daniel Lieberman on Barefoot Running Makes Cover Story in Nature Journal. The study itself can be found at the Skeletal Biology Lab at Harvard University. in Nature 463: 531-5 and Nature 432: 345-352, both in .pdf.
In this study, Dr. Lierberman and his team looked at the difference between barefoot runners and shod runners. They studied and compared those who always wear shoes while running, testing with and without shoes, and those who do not wear shoes while running. The key points from the summary onrunbare.com are:
Higher Impact and Lower Efficiency When Heel Striking: “…running on the heel increases impact (up to three times the impact force of forefoot landing, and up to 7 times the impact loading of running barefoot) and decreases efficiency (causing a braking effect with each stride) while running on the forefoot decreases impact and increases efficiency, by translating stored kinetic energy in the muscles into rotational or forward propulsion.”
Barefoot Runners Lower Center of Gravity to Reduce Impact. “…barefoot runners suffered no greater impact when landing on hard surfaces than soft surfaces… dispels the myth that we could once run barefoot on the Savanna, but cannot do so on harder ‘modern’ surfaces such as asphalt and pavement…”
We Evolved to Run on Our Forefoot. “Natural selection suggests that if endurance running was important to our survival, then forefoot running came about to protect the foot and reduce the chance of injury. While barefoot runners or those who wear minimalist shoes avoid rear foot landings and the associated impacts, in contrast, most shod runners today land almost exclusively on their heels.”
Modern running shoes may be dangerous. “…they promote a heel foot strike, which…produces far greater impact than landing on the forefoot… barefoot running may help reduce the chance of injury…”
The authors and researchers do conclude that more study is needed.
When I used to run, with prescription Brooks Beast, I ran with a heel strike. If I do take up running again, it will be barefoot running with a forefoot strike. To read the articles and educate yourself, follow the links above.