US Patent 7510538 Shoe with energy storage and delivery device

According to the invention, a shoe having at least one base spring element, which is arranged between appendages at a heel zone of the shoe and at a shaft zone taking support at the front edge of the shin bone and which stretches in the course of an ambulation phase, characterized in that a tensioning assembly moves the appendage of the base spring element at the heel zone away from the appendage at the shaft zone upon planting of the shoe, for stretching of the base spring element.