it's interesting that people have been running on grass and dirt, and everything else, long before athletic shoes, or even shoes period were invented, there are l many tribes in undeveloped parts of the world that stil run barefoot, yet they dont seem to suffer too many "sports injuries" maby it's that the high tech shoes have gotten too high tech, I have done distance walking my entire life and I cant even stand modern shoes, I prefer flat shoes, much more comfortable to me, the human foot is a marvel, why do we seem to think it wont work right without special running shoes?