When using the multifunctional fitness chair, first remove the movable armrest, and then there is a six diamond plug at one end of the movable armrest. It is necessary to insert the plug into the jack of the corresponding torsion spring mechanism. When the human body is sitting on the seat, it will use the force of hands, feet, arms and legs to drag or pull the movable armrest back and forth. In addition, everyone can adjust the angle of the backrest according to their own needs, or directly pull out the plug board, turn out the movable board and turn over the support, so that the human body can remain flat, recline or flat