Special insert for shoe has two hard core surfaces in heel and ball area, and special holes in foam surface which with higher pressure loading allow points of hard core surfaces to emerge from holes

摘要

The special insert for a shoe has two hard core surfaces in the heel and ball area, and special holes in the foam surface which with higher pressure loading allow the points of the hard core surfaces to emerge from the holes. The soft foam surface of the insert itself has holes in which are fitted the hard core surfaces. If the wearer steps too heavily the soft foam collapses and the pointed ends of the cores enter the holes of the soft foam surface and remind the wearer that a maximum loading has been exceeded.