In judo I learnt to deflect a punch by pushing on the outside of the forearm (so punch from left = push to my right) and I was taught to then grab the wrist and pivot, following the attacker’s original motion and pulling them off balance. This works great because 1. you’re not opposing their motion, 2. they can’t resist, and 3. they end up with their back to you. But would it ever make sense to grab the INSIDE of their arm? >Not writing: drew a pose which feels off for this reason, and wondered.
Yes… there are even ways to perform blocks that don’t involve your opponent going past you. Judo uses this particular block as a primary foundation because it’s a great for setting up a variety of different throws. The eventual goal is not for this to end with their back to you, but for them to be on the ground. However, that particular block is Judo and there are other blocks with a similar motion that create very different options.
So, does it ever make sense to grab the inside of the arm?
Yes, when you want direct access to their entire body. Yes, when you want to knock them over onto their back. Yes, when you want to grab them by the head and put them into a throw using your front leg. Yes, when you want access to their stomach, chest, and neck. Yes, when you want to go directly from your block into a headbutt. Yes, when you want a straight vector.
You can go up, down, in, out, get onto a variety angles for blocks and deflections depending on the following techniques you’re intending to perform. You can block kicks with your knee/shin/thigh, deflect punches with your hand or your forearm. It all depends on what you’re going to do and what tactics/strategies you’re martial art relies on.
With a inside deflection, knocking your opponent’s arm away, you catch the forearm before the arm reaches full extension and apply opposing force using your wrist rather than your hand to redirect the punch away from you on the same side rather than a cross-block/cross-deflection of lefty/lefty or righty/righty. Doing that inside block opens the body up for direct strikes. You can also gain control of the arm, and the body. Use the opportunity to go right into grappling range, past the point where they can punch you.
There are so many available options that you can do from this position that I really can’t overstate how basic it is. Everything from joint locks, to throws, to pressure points can be done by grabbing the inside of the arm. If you continue with Judo, you will eventually learn what some of these are yourself.
However, what you really want to get rid of from the very beginning are ideas about “the best” or “makes the most sense”. All blocks and all martial arts are situational. There is no best way to do anything, ever. There’s a multitude of ways, and most of them work. You’ll hamstring yourself creatively if you let the fanboy attitude which creeps into martial arts debates take control. Weapons are situational, techniques are situational, blocks are situational. They all have situations where they work and where they don’t. The goal of your training is to expand your horizons so you have a multitude of options available for a variety of situations.
Whenever you ask, “is this the best way?” Know that the answer is, “well, that’s one way.” It may be a good way, but it isn’t the only way. However, it might be the way you chose and if it is then that’s good enough. Just don’t cut yourself off from learning more, and giving yourself more options when your first instinct is “this doesn’t feel natural.” Of course it’s not, you haven’t learned how to do it yet. That’s no reason not to keep looking.