Every BJJ club should have some hours each week dedicated to open mat time.
Yes, you need to attend classes for instruction regularly, especially in your first two years of training jiu-jitsu. You are building your vocabulary of techniques and your instructor should be methodically building your skills by using a progressive curriculum.
Since BJJ games are so highly individualistic, you need time to drill the techniques that you want to make part of your game. If that position is not going to appear in your curriculum in the next two months, how are you going to develop it? You need some open time to drill it.
I believe that in order for you to learn a technique deeply, you need to spend time with training partners figuring it out between you.
You deconstruct the technique:
What is each arm and leg supposed to be doing?
Where should your weight be?
You move your grips a few inches this way and then the opposite.
How does it make a difference?How does your opponent immediately want to counter it?
How can you use action / reaction to set up the technique?
Sure, your instructor can give you all of those answers, but there is value in figuring out things for yourself. You are learning…well…how to learn a technique.
This all takes time that is not readily available in regular classes, unless you are skipping rolling to drill your own things.
That is why open mat is so important. Great training partners are worth their weight in gold, and when you find one, make plans to meet at open mat time and build your own BJJ game.
Some of the best tools you can use at open mat:
1) Drill for reps. I am not talking about half-hearted, going-through-the-motions type of drilling. I’m talking about intentional movements. Look for precision in each part of the movement.
2) Drill until you start to fatigue. Observe where your technique mechanics start to fall apart. This is important because in live rolling, you are going to be tired. Pay special attention to where your technique falls apart once the muscles are tired and the explosiveness is gone.
3) Positional training. Many of the top BJJ champions REALLY believe in positional sparring, especially before competition. Start each roll in the position. Once an objective is reached (ex. the guard is passed or your get the sweep) then reset and go again. Repetition is the mother of skill!
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