Abstract: A device for use in a shoe includes a first foot, a second foot, a third foot, a fourth foot, a first flexible leg, a second flexible leg, a third flexible leg, and a fourth flexible leg. The first flexible leg extends from the first foot and is curved. The second flexible leg extends from the second foot and is curved. The third flexible leg extends from the third foot and is curved. The fourth flexible leg extends from the fourth foot and is curved. The first flexible leg, second flexible leg, third flexible leg, and fourth flexible leg are joined together with each other at a common area. The first flexible leg, second flexible leg, third flexible leg, and fourth flexible leg are configured to store energy when a force is applied to the common area, and to return energy when the force is removed from the common area.

Abstract: A shoe includes a first plate, a second plate, a third plate, filler material, springs, an insole, and a midsole. The first plate and the second plate are hingedly connected to each other. The filler material is located between the first plate and the second plate. The springs are located within openings in the filler material. The third plate is affixed to a top surface of the first plate. The insole is located above the third plate. The first plate is made of a thermoplastic elastomer, and the third plate is made of carbon fiber. Another shoe includes a midsole, a plate located above the midsole, springs located at least partially within openings in the midsole, and a spring holding unit located below the midsole for holding the springs. The spring holding unit includes spring holding members and branches connecting corresponding spring holding members.

Abstract: A device for use in a shoe includes a first foot, a second foot, a third foot, a fourth foot, a first flexible leg, a second flexible leg, a third flexible leg, and a fourth flexible leg. The first flexible leg extends from the first foot and is curved. The second flexible leg extends from the second foot and is curved. The third flexible leg extends from the third foot and is curved. The fourth flexible leg extends from the fourth foot and is curved. The first flexible leg, second flexible leg, third flexible leg, and fourth flexible leg are joined together with each other at a common area. The first flexible leg, second flexible leg, third flexible leg, and fourth flexible leg are configured to store energy when a force is applied to the common area, and to return energy when the force is removed from the common area.

Abstract: A shoe includes a first plate, a second plate, a third plate, filler material, springs, an insole, and a midsole. The first plate and the second plate are hingedly connected to each other. The filler material is located between the first plate and the second plate. The springs are located within openings in the filler material. The third plate is affixed to a top surface of the first plate. The insole is located above the third plate. The first plate is made of a thermoplastic elastomer, and the third plate is made of carbon fiber. Another shoe includes a midsole, a plate located above the midsole, springs located at least partially within openings in the midsole, and a spring holding unit located below the midsole for holding the springs. The spring holding unit includes spring holding members and branches connecting corresponding spring holding members.

Abstract: A shoe includes a first plate and a second plate that are located in a portion of the shoe between an upper and an outsole of the shoe, and a nest formed as a bag filled with one or more gasses located between the first plate and the second plate. The shoe may further include one or more springs located in cavities in the gas filled nest for biasing the first plate and the second plate apart from each other. Pods may be located within the openings in the center of the springs, and the pods may be filled with one or more gasses. The pods may protrude from a bottom or a top surface of the nest. Spring sandwiches including one or more springs positioned between plates may be constructed and placed in various portions of a shoe. The shoe may also include piping with lights.

Abstract: A shoe includes a first plate and a second plate that are located in a portion of the shoe between an upper and an outsole of the shoe, and a nest formed as a bag filled with one or more gasses located between the first plate and the second plate. The shoe may further include one or more springs located in cavities in the gas filled nest for biasing the first plate and the second plate apart from each other. Pods may be located within the openings in the center of the springs, and the pods may be filled with one or more gasses. The pods may protrude from a bottom or a top surface of the nest. Spring sandwiches including one or more springs positioned between plates may be constructed and placed in various portions of a shoe. The shoe may also include piping with lights.

Abstract: A shoe includes a first plate and a second plate that are located in a portion of the shoe between an upper and an outsole of the shoe, and a nest formed as a bag filled with one or more gasses located between the first plate and the second plate. The shoe may further include one or more springs located in cavities in the gas filled nest for biasing the first plate and the second plate apart from each other. Pods may be located within the openings in the center of the springs, and the pods may be filled with one or more gasses. The pods may protrude from a bottom or a top surface of the nest. Spring sandwiches including one or more springs positioned between plates may be constructed and placed in various portions of a shoe. The shoe may also include piping with lights.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a portion of the shoe between an upper and an outsole of the shoe, and a nest formed as a bag filled with one or more gasses located between the first plate and the second plate. The shoe may further include one or more springs located in cavities in the gas filled nest for biasing the first plate and the second plate apart from each other. Pods may be located within the openings in the center of the springs, and the pods may be filled with one or more gasses. The pods may protrude from a bottom or a top surface of the nest. Spring sandwiches including one or more springs positioned between plates may be constructed and placed in various portions of a shoe. The shoe may also include piping with lights.

Abstract: A shoe includes a first plate and a second plate that are located in a portion of the shoe between an upper and an outsole of the shoe, and a nest formed as a bag filled with one or more gasses located between the first plate and the second plate. The shoe may further include one or more springs located in cavities in the gas filled nest for biasing the first plate and the second plate apart from each other. Pods may be located within the openings in the center of the springs, and the pods may be filled with one or more gasses. The pods may protrude from a bottom or a top surface of the nest. Spring sandwiches including one or more springs positioned between plates may be constructed and placed in various portions of a shoe. The shoe may also include piping with lights.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: A shoe includes a first plate and a second plate that are located in a forefoot portion of the shoe between an upper and an outsole of the shoe, and one or more springs for biasing the first plate and the second plate apart from each other. A device for a shoe includes a first plate and a second plate that are installable in a forefoot portion of the shoe, and an energy return member positioned between the first plate and the second plate. A method of using a shoe includes applying, with a foot, a force on at least one of two plates that is positioned in a forefoot portion of a shoe, so as to move the two plates together and increase a loading of a spring, and launching the foot due to the two plates being moved apart by the spring as the foot is being lifted.

Abstract: An athletic shoe includes an upper, an outsole, a pair of hinged plates, and a spring. The pair of hinged plates are attached between the outsole and the upper in a forefoot portion of the shoe, and the spring biases the plates apart, so that energy is stored and returned during a propulsion phase of a gait cycle in a human step. Foam may be disposed between the plates. A shroud may enclose an outer periphery of the plates. An adjustable torsion spring may be disposed in a hinge portion of the plates, and one or more wave springs may be disposed between the plates.