How to make a person loose consciousness when you are fighting them.
There are two distinct ways of doing this.
1. Cut off the oxygen supply to their brain.
2. Cause trauma to their head.
I suppose a third way would be to cause massive trauma to another part of their body, such as severing a limb, gunshot wound or other causing another severe injury. But that aside, knocking somebody out usually involves either of the first 2 methods.
Method 1 can be achieved with a choke hold, knife hand strike to the jugulars or a similar attack to the blood supply to the brain. In my opinion this is the most reliable way of rendering somebody unconscious.
For example, if a BJJ fighter is able to apply a choke hold on his opponent, providing that the opponent does not tap out first, he will generally be able to render his opponent unconscious very quickly.
Method 2 is much less reliable, firstly different people apparently are affected differently by heavy blows to the same area of the head. Secondly, such a blow will cause loss of consciousness by rattling/damaging the brain, causing neurons to misfire or not to work at all. This is a very unpredictable effect.
Over the years I have found the following factors pertaining to method 2:
The amount of superficial tissue damage caused by a blow to the head/face is irrelevant to any tissue damage or trauma to the brain itself, and thus irrelevant to rendering the person unconscious.
A blow to the head will cause more brain tissue damage/trauma at the other side of the head than at the point of impact. IE, a strike to the front will cause the head to rock back, the brain to collide with the back of the skull and therefore cause more damage/trauma to the brain at the back of the head.
Round strikes, hooks, strikes to the temple, side of the jaw, or any other attacks that cause the head and brain to be shaken sideways are much more likely to cause the damage/trauma required to knock a person out.
The ability for the person being struck to keep his head still and from being rocked or shook will greatly affect the possibility of them being knocked unconscious. Therefore, having strong neck muscles (like Mike Tyson for example) greatly reduces your chance to be KO'ed through a blow to the head, because it allows one to absorb these blows without the head/brain being rocked too hard.
Concluding, I would say - the most reliable way to render somebody unconscious is to interrupt their blood supply to the brain. IE: a properly applied choke hold. Boxers or stand-up fighters usually have to hit each other in the head many times before one of those hits is able to cause a KO.
Method 3 - controversial. Rendering somebody unconscious by attacking nerves on their body.
This idea was first brought up by Dillman and the Kyushojutsu section of MA. If you want to discuss Kyushojutsu and/or Dillman I'd be happy to do so, but that will require a whole new thread and a lot more of my time.
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