Abstract: An injection molded article has at least a first portion with a first cross sectional thickness and an integral second portion having a second cross sectional thickness. A plurality of hollow projections extend into the second portion, thereby allowing the second portion to have an overall cross sectional thickness substantially greater than the first portion thickness.
Abstract: A midsole comprises a heel cup having a semi-rigid upper plate, a lower plate composed of a material that is softer than the upper plate, and at least one telescopic shock absorber between the upper and lower plates. The telescopic shock absorbers have one portion that collapses into a second portion when the shock absorber is loaded or compressed. On release of the load, the shock absorbers of the invention return only a controlled portion of the compressive load originally applied. A second embodiment has a translucent heel cup and shock absorbers and a lamp for illuminating the heel cup and shock absorbers.