US Patent 9332805 Shoe sole with energy restoring device

The present disclosure describes a performance enhancing shoe sole that includes an anterior support structure and a posterior support structure that are connected by a first support structure. The anterior support structure and posterior support structure are flexible bent spring structures. The first support structure provides a plantar interface that includes a midfoot arch. The shoe sole is positionable in a shoe to provide shock absorption and controlled energy return from the posterior support structure to the first support structure. The shoe sole is an interconnected bent spring system that can be a single ribbon of flexible material defining multiple pivot angles or a multi-layered cantilevered flexible bent spring. The shoe sole can also include inserts that dampen shock.