Abstract: This invention relates generally to footwear such as a shoe, including an athletic shoe, with a shoe sole, including at least one removable midsole section formed by a midsole portion, wherein the removable midsole section is non-orthotic. The removable midsole section is inserted within the shoe upper, the sides of which hold it in position. The shoe sole includes a concavely rounded side or underneath portion, which may be formed in part by the removable midsole section. The removable midsole section may extend the length of the shoe sole or may form only a part of the shoe sole and can incorporate cushioning or structural compartments or components. The removable midsole section provides the capability to permit replacement of midsole material which has degraded or has worn out in order to maintain optimal characteristics of the shoe sole.

Abstract: Footwear, particularly athletic shoes, that has a sole structure copying support, stability and cushioning structures of the human foot. Still more particularly, this invention relates to the use of the shoe upper portion to envelop one or more portions of the shoe midsole in combination with portions of the shoe sole having at least one concavely rounded portion of the sole outer surface, relative to a portion of the shoe sole located adjacent to the concavely rounded outer surface portion, and at least one convexly rounded portion of the inner surface of the midsole component, relative to a portion of the midsole component located adjacent to the convexly rounded portion of the inner surface of the midsole component, all as viewed in a frontal plane cross-section when the shoe sole is upright and in an unloaded condition.