A sole construction for supporting at least a portion of a human foot and
for providing energy storage and return is provided. The sole
construction includes a generally horizontal layer of stretchable
material, at least one chamber positioned adjacent a first side of the
layer, and at least one actuator positioned adjacent a second side of the
layer vertically aligned with a corresponding chamber. Each actuator has
a footprint size smaller than that of the corresponding chamber, and is
sized and arranged to provide individual support to the bones of the
human foot. The support structure when compressed causes the actuator to
push against the layer and move the layer at least partially into the
corresponding chamber. In one embodiment, dual action energy storage and
rebound is provided by using a plurality of actuators that move both
upwardly and downwardly into corresponding chambers. In another
embodiment, lateral stability is improved by using tapered actuators
having a convex shape to accommodate the natural rolling movement of the
foot.