COMPRESSIBLE STRUCTURE SECURED TO AN UPPER OF AN ARTICLE OF FOOTWEAR

摘要

An article of footwear has an upper and a compressible structure secured to the upper. The compressible structure can include one or more materials with physical properties that singly or in vertical aggregate, generally conform to those of a spring, following Hooke's Law, F=-kx, whereby the ratio of k/k_ideal approaches a value of 1.0, wherein the ideal k value is defined as k_ideal=F_impulse/x_s-max, for a compressible structure region located adjacent to the corresponding region of the foot that generates the force impulse.