Shoes, devices for shoes, and methods of using shoes

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.