Abstract: The present invention is devices and methods for indicating, to a wearer of a shoe, a loss of shock absorption in the shoe so that the wearer can know that it is time to obtain new shoes and thereby avoid injury. The devices and methods of the present invention indicate a loss of shock absorption as follows. First, one or more sensors in the sole of the shoe detect the amount of force that is applied to the sensors while a wearer's body weight is pressing down on the shoe. Then, when a sufficient amount of force is detected by the sensors in the sole of the shoe, the sensors provide a warning to the wearer of the shoe that the shoe has lost its shock-absorbing capability.