The invention relates to the field of shoes in general, and more specifically to the application of microspheres in shoe material formulations to yield desired shoe properties. Even more specifically, the invention relates to a shoe component prepared from a closed cell foam incorporating microspheres to yield controlled cell size, cell size distribution and expansion characteristics. In another embodiment, the invention also relates to an inner sole for a shoe prepared from the reaction product of a polymer matrix component and a curing agent where the curing agent is incorporated in microspheres to yield a material conformable to the user's foot shape.