An example exercise system includes an exercise apparatus including a processor, a movable element and an output device and a device including a processor and coupled to the exercise apparatus and to a communication network. The leg part has an elastic coupling claw projecting outward from the pass-through part to be coupled in the panel hole, and a turn lock part. A clip is engaged between the facing surfaces and is slideably movable in the guide track between an open position such that the archwire slot can receive an archwire and a closed position in which the clip can retain the archwire in the slot. The support unit may be implemented in a variety of ways, and may be one of many support units.