• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

sos need some info

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.


New Member
Mar 26, 2002
Hello to all who inquired into my distress signal,
I am a nursing student doing a paper on effects of oxygen deprivation. I became curious about the static apnea divers. I have read conflicting accounts on the world record for this sport. One was 8 min 9 secs, the other 7 min 35 secs. I would like to know how this is possible, the training that goes into it, and are there any long term effects to this. All help would be greatly appreciated. You have my admiration. Wow!!
Diving reflex

Hi there!
to most people in the freediving, human are descendent of water mamal (see Jacques Mayol book homodelphinus http://www.deeperblue.net/content/2002/freediving/homodelphinus/1.shtml ). Thus, like the dolphin, seal, etc... we have a dormant diving reflex. Basicly, the blood flow concentrate on the noble organ (heart, brain, liver etc..) when doing an apnea (hold breath). To do 8m06- like Martin Stepanek, AIDA world record holder, you need to do a series of breath hold, which will awake this diving reflex (By the way, in competition, because of the stress , people normally do 1 min less then their best time...). Immersing the face in cold water really help too. Follow this link ( to see a video of Howard jones doing and explaining apnea to doctors. He actually flatten a heart rate machine (electrocardiogram). And by the way, thank for the admiration, but you should join us, you got the reflex too, the sleeper must awake (Dune). Good luck!!!
Hello Tamilu,

Apnea (breathold) is the difference between hypoxia and apoxia. What Howard is experiencing while holding his breath in the referenced video is hypoxia (low O2 levels in the bloodstream). Apoxia is no O2 in the bloodstream (virtually) and you probably know more about this as medicine is your gig. What CF referenced about the SCUBA diver being revived after a long period is apoxia combined with a slowed metabolic rate induced by low temps. You probably have read of this being used during surgery. With apoxia, brain damage occurs within minutes. With Hypoxia, brain damage is already firmly in place as all who visit these forums are aware:D

Seriously, studies done on low O2 blood levels during breatholds have not provided significant data to indicate hypoxia is harmful.

Now, repeatedly blacking out is a different story. Apoxic states are reached after blackout. Blackouts may indeed be harmful when consistantly experienced over many years.

Keep in mind, I am a Builder who has listened, discussed and read alot about this subject tobe safer at my favorite activity. HOWEVER, please verify what I have stated above. Medicine and physiology are not my areas of expertise-construction is.


Hi Tamilu, I might add that there is evidence from experiments with animals, that repeated exposures to low 02 levels actually is good for them (and us). Microcapillary growth occurs, improving circulation and cardiovascular ability. Similar to moving to extreme altitude for a while.
At least I hope so ;)
The "Mammalian Dive Reflex" that the Frenchman is talking about can occur 2 ways, that I know of. One is to submerge to a substantial depth on one breath: this compresses the lungs, starts the bloodshift, shunting blood from the limbs and constricting the arteries that feed them, activates hemoglobin release stored in the spleen, and induces bradycardia.
The second way is to do 3 or 4 breath-holds at the surface, usually holding them to the point of involuntary diaphragmatic contractions (up to 50), which also will activate the spleen.
In my case, after a week of doing more than 5 breath-holds in a row, per night, I can hold my breath at anytime and feel the blood shunting out of my limbs. I have talked to other divers who experience the same thing. Eric Fattah, who has dived to 89 metres on one breath, has a reaction to stress that is similar to that of the Weddel seal: his heart rate DROPS when under stress, as opposed to the normal human reaction of adrenalin surge and increase of BPM.
Erik Y.
Thank-you all who replied (sos)

I would just like to thank the wonderful people who responded to my sos. The help so far has been very enlightening. I would also like to commend you all for the astonishing abilities you possess. Who knew?? lol A few of you have suggested that I try it, being a 38 year old smoker (i know) i don't think i would have a chance in you know what. Again thanks for all the replies, and keep them coming. You are a great bunch of people.:)
  • Like
Reactions: Erik
I just saw that one of your original questions was unanswered.

World records:

There are several bodies that ratify world records, and the quotes of 8:06 and 7:35 come from the same ratifying body. One is the old world reord from that body and the other is the new world record (set mid-last year).

DeeperBlue.com - The Worlds Largest Community Dedicated To Freediving, Scuba Diving and Spearfishing


ISSN 1469-865X | Copyright © 1996 - 2024 deeperblue.net limited.

DeeperBlue.com is the World's Largest Community dedicated to Freediving, Scuba Diving, Ocean Advocacy and Diving Travel.

We've been dedicated to bringing you the freshest news, features and discussions from around the underwater world since 1996.