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A question - please be patient!!

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Phat not fat!
Feb 12, 2002
Sorry if my questions seem really trivial, but I am trying to get my head round something that is totally new to me.

Starving the body (and brain) of O2 is something that is linked to brain damage. Now I realise that my pathetic attempts of breath holding are not long enough to do any real damage. You guys talk about sambas and black out quite frequently. Is any long term damage sustained because of these even if it is very minor?

Thanks again for your help

Automatic switch off

IMHO, when you samba or suffer SWB, it's because your brain protect itself from the lack of oxygen by shutting down. As for brain damage, the average people breath very badly, and their brain is lacking oxygen most of the time. On the other and, the freediver do a lot of breath up where the brain can get all the oxygen it needs so i would be tempt to say that freediving is GOOD for your brain cells.
Brain damage...

Brain damage doesn't happen before blackout but about 4minutes after that...
Read the article about Myoclonus and Hypoxia or "Sambas" and "Blackouts"
there these phenomenons are explained well
This is from that article:by Peter Sheard

There is debate about how long the brain can go without oxygen before incurring irreversible brain damage. The critical threshold for the minimal oxygen level necessary to result in brain damage is surprisingly unknown. The consensus is that when there is a lack of blood flow to the brain for more than 3-4 minutes, brain damage will be fairly generalised throughout most major structures of the brain. Contradicting this are reports of 10 - 40-minute accidental submersions from which there has been full recovery (Gooden 1992). However, in most cases where submersion exceeds 10 minutes the chances of recovery without neurologic impairment is low (DeNicola et al. 1997).

All questions are good;)
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