A sole component for footwear formed as a single bladder chamber in contact
with an elastomeric midsole, or a single chamber formed by a sealing a
void in elastomeric material. The interface between the chamber and
elastomeric material is sloped and gradual so that the shape of the
chamber and its placement in a midsole determine the combination of
response characteristics in the sole component. The chamber has one axis
of symmetry with a rounded portion and a narrow portion. The chamber has a
relatively large volume, is devoid of internal connections, and has an
internal pressure within 5 psi of ambient pressure, and preferably at
ambient pressure. Since air is used as the fluid, no specialized gases are
required. No specialized films or bladder materials are required where the
chamber is formed as a bladder, since the bladder is not highly
pressurized.