Is 7-ups physics theory correct?
I just read 7-ups theory on the V-stretch. This is it cut and pasted
“a 10 pound force suspended from a cord exerts only 10 pounds of force within the fibers of the cord. BUT anchor the cord from 2 ends and place the 10 pound mass in the center….and the tension within the cord increases very greatly. For example, you may hang from a clothes line tied to a tree branch. But if you try to hang from the same cord when it is stretched between 2 clothes line poles, it will break under your weight. The tension within the clothesline exceeds the tensil strength of the rope. That is the theory.”
I will have to read through some physics books again but I do not think this is correct, I cant understand how the rope will break easier on 2 line poles with the same weight. Maybe my interpretation is wrong. I would like to do more calculations to see what angles are best and the possibilities of several weights going up and down like a system of pulleys. As a manual stretch you are limited at the end by the max force you can hold, so what arrangement of other weights is best? Some body builders may tell us what arm position is best for long holds of equivalent weights.
I am by no means saying it doesnt work, I have done the Vstretch and it does feel like a lot more strain on the ligs.