The present invention relates to an improved structure of a treadmill, more particularly, to a frame structure of an electrical, collapsible treadmill. A guidance holding unit holds guidance information for voice output for each of the plurality of setting values. A barrel is coupled at one end to the coupling mechanism. The sliding block is slidable along an arcuate path between a first position in which the second roller engages the first region of the contact surface and a second position in which it engages the second region of the contact surface, so that, when the sliding block is in the first position, the pivot joint remains stationary, and the valve remains closed.