I was recently asked why arm bar’s are so effective. These questions usually come from people who have not experienced arm bars – one of the most effective submissions moves in grappling. This time however, I thought about the anatomy of it and the effect this might have had on the exercise world.
An arm bar, correctly applied, usually causes a tap out within a few moments. If you can imagine lying on the ground. Your opponents legs are across your chest and neck, effectively pinning you to the ground. Your arm is extended between their leg and your hand held palm up on their chest. This might already be causing you some physical discomfort depending on the flexibility of your shoulder and the size of your opponent. Now they start to push their hips up. The discomfort escalates as your elbow is forced to hyper extend. You are not getting out of it and most people tap out.
Why does it hurt? Just look at the connective tissue around your elbow.
Every ligament and tendon is filled with receptors that you usually use to help locate them in space. They constantly feed back information to your brain that tells it how much stress it is feeling or how quickly it is accelerating. The brain can calculate which direction things are moving in by comparing the messages from different parts of the body. And it does all of this without you even thinking about it.
Have you ever fallen asleep when you shouldn’t have and woken up with your head jerking back? You probably thought you work up and jerked your head up to appear awake. It happens the other way around. When you fall asleep your head will tip forwards as the muscles relax, due to its weight. This causes the muscles and connective tissue at the back of the neck to suddenly be stretched. That sudden stretching sends a message to the brain ‘We are stretching too quickly, slow it down.’ The body slows that down by contracting the muscles that oppose that stretch. This causes the head to jerk back up and that it what wakes you up. Your body took care of its self whilst you were asleep.
As the muscles and connective tissue start to get stretched in the arm bar the brain gets the same messages. ‘We are being too stretched’ Only the arm is trapped, it can’t do anything to reduce that stretch.
Two bones make up the forearm; the radius and the ulna. The ulna has a large hook like prominence that makes up the point of the elbow. When you straighten your arm, this prominence fits into a hollow at the back of the humerus, the bone of the upper arm. If you continue to extend it then the bone can go no further, it is blocked up the humerus. I’m told it is very unusual to break this prominence off of the ulna by using an arm bar – the usual injury is a dislocated elbow. Either way it is painful.
But what does this have to do with the exercise world?
Have you every gone to a legs, bums and tums class. Endless squats but usually also endless bridges. You lie on the ground, feet close to your butt, and push your hips up as high as you can. A great exercise for the glutes but where do you think it came from? The origins of the bridge can be traced back to ancient Greece and wrestling. The easiest way to get off someone who is on top of you is to push up your hips. The best way to get a submission is to apply an arm bar. The best arm bar will be applied with the highest hips. We might use the exercise now to get a shapely bum but that isn’t why it was developed.
Janet has a PGDip in Anatomical sciences and is currently studying for a PhD looking at different groups beliefs about the body. She represented the UK in TKD and learnt grappling as part of her Budokon belt system.