ABSTRACT
The load sequence of running is characterised by an impact peak in which the heel area of the shoe is, within few milliseconds, loaded with twice the runner’s bodyweight. Thereby, the shoe midsole, usually made of flexible foam, reduces this impact to a physiological harmless level by absorbing energy while being deformed up to 45% of the initial thickness. It is assumed that a portion of this energy as a result of compression by the pressure of the foot is dissipated as heat. This heat would influence the properties of the midsole material due to the temperature dependency of flexible foams. According to Heidenfelder (2004) energy absorption and functional stiffness of running footwear decrease while temperature increases.
