I was spending quite a bit of time in Jackwood website these day...
He had mentioned a few times how the Portable Power Jumper can improve vertical for him , and even for the program51 author...
the original one is here:
![](http://www.xlr8europe.com/uploads/Portable-Jumper-lg(1).gif)
![](http://i.pgcdn.com/pi/74/94/13/749413316_260.jpg)
There is also a less expensive version for people with back injury...
![](http://i.pgcdn.com/pi/74/82/83/748283349_260.jpg)
Being not in the state.. i try to look for alternative for fun..
I did found some copy cat version of the less expensive waist attached version
(notice the ankle connection)..
but since JackW suggested the complete system (rope on the back), I wonder if it is possible to DIY... by using those Foot work ankle warp and additional power rubber band...
$5 USD
![](http://cdn100.iofferphoto.com/img3/item/508/178/478/joinfit-leg-strength-training-resistance-bands-tensile-d6e1.jpg)
![](http://cdn102.iofferphoto.com/img3/item/508/178/478/joinfit-leg-strength-training-resistance-bands-tensile-f1ff.jpg)
+
$10 USD
![](http://images.bizrice.com/upload/20120203/Portable_Latex_5_Resistance_Fitness_Exercise_Power.jpg)
The main problem is, the ankle wrap might be easily slip up on the leg
(what do u guys think?)... unless it is warped from bottom up around the sole..
Another problem is, I have to source a rubber cable with the right length..
but the final or the first question is.... Is this equipment as worthy as jackw suggested... or another waste of $ & time product...