Abstract: A shoe sole and shoe are provided for offsetting a wearer's side-to-side balance to encourage a wearer's conditioning and toning. The shoe sole includes a midsole width that underlies and supports a wearer's foot, and an upper midsole portion undercut at its peripheral sidewall around the heel to define a horizontal indentation. A lower midsole portion has a corresponding “undercut” in its upper surface that angles downward and outward from the indentation. The depth of the indentation forms a balancing portion between the medially and laterally placed indentations that is narrower than the midsole width, thereby forcing the wearer to adjust one's walking gait to maintain balance over the balancing portion. A structure with a base portion can be disposed along the indentation with upward and or downward extending extensions disposed along the peripheral sidewall. The structure can include leaf springs extending transversely over a central midsole portion.

Abstract: A shoe sole and shoe are provided for offsetting a wearer's side-to-side balance to encourage a wearer's conditioning and toning. The shoe sole includes a midsole width that underlies and supports a wearer's foot, and an upper midsole portion undercut at its peripheral sidewall around the heel to define a horizontal indentation. A lower midsole portion has a corresponding “undercut” in its upper surface that angles downward and outward from the indentation. The depth of the indentation forms a balancing portion between the medially and laterally placed indentations that is narrower than the midsole width, thereby forcing the wearer to adjust one's walking gait to maintain balance over the balancing portion. A structure with a base portion can be disposed along the indentation with upward and or downward extending extensions disposed along the peripheral sidewall. The structure can include leaf springs extending transversely over a central midsole portion.