Patent ID: 6860034

Claim:
An article of footwear comprising: an upper; a sole having a ground engaging portion and an energy return system between the upper and the sole; the energy return system comprising: an upper plate and a lower plate spaced a predetermined distance from each other, the upper and lower plates having heel, arch, and toe portions, respectively, and made from an elastic material of high tensile strength, the plates independently deformable and recoverable from heel portion to toe portion; and two elastomeric elements, one disposed between the toe portion of the plates and the other disposed between the heel portion of the plates to maintain the spacing between said plates during a gait cycle of a wearer comprising a heel strike, a midstance, and a toe off; during heel strike the heel portion of the upper plate deforms downward and the arch portion of the upper plate deforms upward; during midstance the arch portion of both the upper and lower plates deforms downward and the heel portion of the upper plate recovers to a non-deformable state rocking the wearer forward; and during toe off the upper and lower plates recovers to the non-deformable state releasing stored energy into a step forward and upward propelling the wearer forward.