Multi-functional exercise machine

A multi-functional exercise machine, comprising a slide rail piece, a support piece and a handle supporting piece:

• the slide rail piece is slidably connected with a slider which is slidable on the slide rail piece:
• a seat cushion is mounted on the slider:
• a second connecting piece pivotally connected with the support piece and a first connecting piece pivotally connected with the handle supporting piece are fixed at one end of the slide rail piece, the first connecting piece and the handle supporting piece are both provided with first knob holes corresponding to one another, and a first knob is detachably mounted through the first knob holes;
• the second connecting piece is provided with an adjusting groove;
• a first positioning point and a second positioning point are formed on the adjusting groove, the support piece is provided with a bolt hole corresponding to the adjusting groove, a pull pin passes through the adjusting groove and the bolt hole, and the pull pin is movable in the adjusting groove and is fixed at the first positioning point or the second positioning point;
• when the pull pin is fixed at the first positioning point of the adjusting groove, the support piece is parallel to the slide rail piece;
• when the pull pin is fixed at the second positioning point of the adjusting groove, an included angle smaller than 180° is formed between the support piece and the slide rail piece;
• the handle supporting piece is connected to a handle;
• pedals are mounted on the support piece. a damping piece is also mounted on the support piece, one end of the damping piece is connected to the support piece. and another end thereof is detachably connected to the handle supporting piece.