Manualy Eccentric Overload

Manul eccentric overload without weights:

Trapezious Shrug:
Use barbell that is attached to floor (platform) with chain at star position height, pull “up” to top position so your knee bent (pull body towards ground) then press with legs up. Whole time your applying max force with trapezious but pressing up with legs overcome that force and muscle is lengthening under tension.
Duration of eccentric can be adjusted with control of applyed leg force.
I used 4 sets of 5 seconds (20 sec. total) and 5 sets as fast as possibile.
Short duration max force appled is to target IIa and IIx fibers.

I messured isometric pull at star position of shrug with dynamometer before and after 10 sessons doimg this exercise and force produced went up for wery good amount.
Expirience some DOMS in first sesson but strength went up.

Same can be done for OHP/BNP, biceps curls, triceps exstension, high pull,…

This is one of those times that just posting a picture can make a big difference.

You said you measured it, meaning a quantitative metric; instead you qualified your setup…
How much was the increase in load?