It's about pressure, not about blood flow. Notice that guys who are calm tend to take longer to pass out, all other things being "equal."
Here's an interesting article that discusses the anatomy of strangulation and how breathing and overall arousal may affect the effectiveness of a technique:
In the "rock, paper, scissors" on credibility on anatomical processes I'll side with anatomical and medical science v. an article by Scott Sonnon that lacks any citation other then another article that he himself wrote.
Cerebral iscemia and cerebral hypoxia are simply stronger, more thoughly tested explaination of the effect of vascular strangulation then Sonnon's suggestion of blood pressure variability being the key to the effect. If he or you have better citations I'd love to read them however.
Anatomy of a choke Pt. 2
To follow up on my original thread here here's a video displaying some of the bodies reactions to the initial shock from lack of oxygen to the brain.
what idiot let himself get choked lol.
many "idiots" have
Originally Posted by Shadowdean
its very educational
personally i have never been totally unconscious, but i would have had to have been close. felt like i was swimming through jelly, i could barely lift my arm to tap out
yet 30 seconds later i was ready to continue sparring.
lots of new people/ younger people in judo class freak out the first time they are in a choke hold. getting a choke put on them in a very controlled way takes the mystery away from it, and they dont panic anymore.
so please think before making more ignorant judgements
[quote=Shadowdean]what idiot let himself get choked lol.[/quote]
edit: hmm... tags worked in preview but not in actual post...
On a more serious note, I agree with Roly. Chokes can be very intimidating/panic-inducing for people who aren't experienced.
Also, many people who do not actually train in a grappling art (and probably experienced a sloppy shchool-yard headlock at best) grossly underestimate the efficacy of a good choke/strangle-hold. That is, until they experience it first hand.
Last edited by Deadmeat; 7/10/2007 9:11pm at .
Reason: tried to fix the picture
Sonnon is NOT the "only person" espousing this view. His article was simply the first one I could google up that intelligently explained the theory.
Originally Posted by Fitz
Judo legend Mark Tripp himself stated:
Subject: RE: INFO
Date: 30-Apr-00 | 07:57 AM
"When you use Hadaka-Jime to manipulate the gall bladder meridian, you are cutting off blood flow to the brain. No magic involved, just Biology and Physiology. "
Actually; that is not correct. There are various places on the web where Judo's art of Shime-waza is discussed at great length.
You will find that it is about blook pressure not blood flow that is the reason the person passes out; and that the gall bladder doesn't have a thing to do with it.
Someone will post the site, I am sure."
Full text of discussion here: http://members.tripod.com/stickgrapp...mtcombat5.html
Here's another tidbit from E.K. Koiwai, M.D.:
"Considerable scientific research has been done by the Japanese. These results are published in two reports of the Bulletin of the Association for Scientific Studies on Judo, Kodokan, in 1958 and 1963. They studied the physiological effects of choking in Judo by using the electroencephalogram for brain wave changes, the earoxymeter for blood oxygen saturation, the sphygmamometer for arterial blood pressure, the plethysmograph for reaction of peripheral blood vessels, the micro-pipometer for skin temperature changes. Others also studied the plasma protein concentration, blood water volume, hematocrit, complete blood count, eosinophil count, and urine 17 keto-steroid content. They were, of course, interested to know if there were any deleterious effects during and after the shime-waza was applied and what precautions should be taken to prevent any serious consequences.
The following are some of the conclusions made based on their experiments with human subjects and animals.
- Unconsciousness occurs approximately 10 seconds (8-14 seconds) after choking. After release from the choke hold, the subject regains consciousness naturally (spontaneously) without difficulty in 10-20 seconds.
- In hadaka-jime the pressure on the larynx and trachea produced excruciating pain but there was no pain in other techniques before unconsciousness.
- The unconsciousness resulting from choking in Judo is mainly due to lack of oxygen and metabolic disturbances created in the brain, as a result of disturbance of cerebral circulation.
- The appearance of flushing of the face is due to disturbance in pressure in the carotid arteries and jugular veins.
- When convulsions occur, the EEG findings are very similar to a very short epileptic seizure.
- Tachycardia (increased heart rate), hypertension (increased blood pressure) and mydriasis (dilation of the pupils) were caused by stimulation of the sympathetic nervous system (vagus nerve).
- Tachycardia and hypertension may be also attributed to the carotid sinus reflex.
- All other laboratory studies show changes that are similar to condition accompanying central shock. Choking in Judo acts as a stressor on the circulator and hypophysio-adrenocortical system.
According to their experience, no deleterious after effects remain after being "choked".
It is considerably less dangerous than a "knock-out" in boxing and there is no necessity of completely excluding "choking" from Judo, provided necessary precautions are taken. "
Full text of article: http://www.judoinfo.com/chokes2.htm
The highlighted text above repeatedly indicates changes triggered by changes in blood pressure, which may be aggravated by heightened arousal (sympathetic response -> panic, basically). Note that references to the "carotid sinus reflex" also imply the importance of pressure changes.
Here's info on the carotid sinus: http://en.wikipedia.org/wiki/Carotid_sinus
Further info on the carotid sinus reflex and hypersensitivity: http://www.emedicine.com/med/topic299.htm
Note that the last reference also explains why some people have had to be dismissed from training because they pass out too easily.
I have had extensive training in anatomy, physiology, and pathology, including many hours of cadaver lab work. Based on my study of relevant peer-reviewed texts and discussions with my instructors, I feel that blood pressure outweighs blood flow as a contributor to passing out. Yes, alterations in blood flow can dramatically affect blood pressure, but ultimately it is the change in pressure that triggers shut-down.