A shock-absorbing running shoe has a sole attached to an upper, with a carriage in the upper adapted to receive the rear portion of a runner's foot. The sole has a collapsible area below the carriage. A first strut is attached to the instep side of the sole and extends above the carriage, and a second...http://www.google.co.uk/patents/US6131309?utm_source=gb-gplus-sharePatent US6131309 - Shock-absorbing running shoe
