is attached to an upper transverse member 82 which is foldably secured via a hinge 83 to the upper latitudinal member 146 a vertical rest 132 is slidably secured in a parallel configuration to the third upright member 143 a horizontal bar 128 with adapting holes 126 slides into the upper transverse frame member 82 through a tunnel 127 the horizontal bar 128 is then secured in place by a screw 85 which fits into one of the holes 126 all three upright members in this embodiment are equipped with support platforms 92 at the bottom still referring to fig1 a pulley sheave 102 is movably secured to a hook 98 which is mounted to a vertical support member 94 which is slidably attached to the top horizontal frame 142 holes 96 provide means to receive screw 95 for positioning the vertical support member 94 at a desired position the vertical support member is placed near the median sagittal plane of the device 90 a first flexible cord 104 passes over the pulley sheave 102 the lower end of the cord 104 is secured through a rod to a weight holding device 149 weight holding device 149 has a transverse support member 101 with two rods 104 for holding removable weights 106 while resting weight holding device 149 sits on a horizontal member 81 near both ends of the transverse support member 101 are two cylindrical tubes guiding the up and down movement of the weight holding device 149 by sliding along the.