The “Squeeze” in Jiu-Jitsu or any other grappling art is the ability to isometrically ramp. Very often, you will see beginners try to choke and squeezing as hard as they can before burning out and letting go?
Isometric ramping is a skill that takes many many years to master. That is why you see so many long time practitioners with impressive squeeze when they apply submissions or hold a tight bodylock.
Eddie Bravo talking about the proper way to train the squeeze and how IMPORTANT it is to your game:
Stephan Kesting has 5 drills you can do on a heavy that will develop your ability to really put the squeeze onto your opponent when you’re grappling.
The side control squeeze
Body lock squeeze
Closed guard squeeze
Triangle squeeze
RNC squeeze
You can also check out this:
Simple Ways To Develop Your Squeeze For Jiu-Jitsu Chokes