It has long been an object of shoe designers to provide wearers with an optimum combination of comfort and support. Problems addressed by the prior art include: cushioning impacts against the pavement or other walking surface, preventing pronation, and providing support to promote a natural gait. The various elements employed by shoe designers to promote these and other ends include heel plugs, shanks, and contoured soles. Heel plugs and other similar devices used to cushion walking are known in the art. See, for example, Haag, U.S. Pat. No. 1,724,349, and McMahon, U.S. Pat. No. 4,342,158. Shanks of various shapes are known. See, for example, Browne, U.S. Pat. No. 819,845. However, it is not known in the prior art to embed a dynamic rocker element in the midsole, nor is it known in the prior art to combine these with heel plugs and shanks or similar elements to take advantage of any structural interaction they may have.
USPTO Backgrounds
USPTO Backgrounds