An article of footwear including a sole and an upper with an exterior and
interior surface, and one or more bladders which comprises at least one
of the exterior or interior surfaces of the upper. The article of
footwear also includes a inflation mechanism located under the foot of
the wearer to be activated by the normal action of the wearer to inflate
the one or more bladders. The inflation mechanism may be monolithic with
the bladder or may be a satellite inflation mechanism coupled to the
bladder. The article of footwear may also include a deflation mechanism.
The deflation mechanism may include a release valve capable of remaining
in a open position and/or an adjustable check valve. The deflation
mechanism may also be a combination check valve and release valve
accessing a single opening in the bladder.