“Given that the human lineage evolved many adaptations in the lower extremity to walk and run barefoot, one should not be surprised that humans run more economically either barefoot or in minimal shoes than in standard shoes. During the last few decades, shoe manufacturers have made running shoes more comfortable by using stiff soles and adding arch supports, but it is possible that these features interfere to some extent with the natural function of the foot. Most elite runners use lightweight minimal footwear with flexible soles and minimal arch support when they race, and average runners may also reduce their COT by going either barefoot or in shoes that allow the foot to function more as it evolved to do.”
http://barefootrunning.fas.harvard.edu/
This is an excellent video about barefoot running.
