-
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!
Hyperventilation vs Purge breath?
- Thread starterbengreen
- Start date
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.
It can take a long time to get an up-to-date response or contact with relevant users.
They are the same thing. Its a matter of degree. Modest purging seems to be ok, mostly, if you haven't been breathing deep and slow before hand. That is also HV and the two together is way too much. Purging works to lengthen the dive, especially for less experienced divers, but its not as safe as no HV at all. With training, you can learn to handle the higher co2 levels that come from no HV at all. Takes some practice, but your dives can get longer and longer and be much safer.
Personally, my breathups involve very low ventilation volume, tiny breaths toward the end, ending with a couple of half lung purges. I think I will eventually dispense with the purges. When conditions are good, I'm getting quite long dives(for me), 1.5-2 minutes in 60 -80 ft.
Personally, my breathups involve very low ventilation volume, tiny breaths toward the end, ending with a couple of half lung purges. I think I will eventually dispense with the purges. When conditions are good, I'm getting quite long dives(for me), 1.5-2 minutes in 60 -80 ft.
Agree completely, cdavis. Only thing I'm unsure about is that you seem to be advocating UNDER ventilating, 'hypoventilation', if I understand correctly.
re OP, here's my understanding:
Hyperventilating literally means 'breathing too much', i.e. deeper or faster (or both) than the body needs at that moment.
Purging is a forceful exhalation and a passive inhalation. The intention is (amoung other things, but the relevant one here is) to clear out the stale air in the lungs so that you go down with a tank full of fresh air.
So purging IS hyperventilation.
But go back to first principles. Why is HV a problem? Because it reduces blood CO2 which, in turn
It takes time for HV to effect the blood because it takes time for your body's blood supply to circulate past the lungs and interact with the gases in the lungs, the composition of which has been altered by HV.
Try this thought experiment:
I use my magic powers to transform the air in your lungs to pure O2, just for the last few minutes of your breathe up. Oh no! Without even knowing it you're offloading WAY more CO2 than normal, effectively hyperventilating. Now imagine I do it just for a second. Less of an effect obviously. Or a thousandth of a second? Hell I could turn that air into laughing gas and if it was only for a thousandth of a second, it probably wouldn't affect you.
Point is that time is a factor.
How many people do 5:10 breathing?
I know divers that do 5:10 breathing for a minute or two before the dive, then claim they can resent the blood CO2 by, "throwing in a tidal breath to stop HV", (I've got that in writing from a qualified freediving teacher). But they won't do purge breaths because, "that's HV". Don't make the mistake of thinking HV = fast breathing.
You can do three purge breaths in maybe 5 seconds, and gas composition in the lungs only changes with the inhalation of the second one. If it takes about a minute for blood to circulate then AT MOST 10% of the blood is exposed to the mildly altered CO2 level in the lungs, and then only for a few seconds.
So yes that's HV but it's a TINY amount.
Whether that effect is offset by the benefits of purging is another question.
Personally I've moved away from purge breaths in favour of relinquishing all conscious control of the breath and focusing instead on relaxation and calming the mind.
re OP, here's my understanding:
Hyperventilating literally means 'breathing too much', i.e. deeper or faster (or both) than the body needs at that moment.
Purging is a forceful exhalation and a passive inhalation. The intention is (amoung other things, but the relevant one here is) to clear out the stale air in the lungs so that you go down with a tank full of fresh air.
So purging IS hyperventilation.
But go back to first principles. Why is HV a problem? Because it reduces blood CO2 which, in turn
- reduces the urge to breathe, making blackout easier,
- slows the dive response,
- and decreases pH of blood, adversely affecting O2 carrying capacity of hemoglobin.
- ...did I miss anything gang?
It takes time for HV to effect the blood because it takes time for your body's blood supply to circulate past the lungs and interact with the gases in the lungs, the composition of which has been altered by HV.
Try this thought experiment:
I use my magic powers to transform the air in your lungs to pure O2, just for the last few minutes of your breathe up. Oh no! Without even knowing it you're offloading WAY more CO2 than normal, effectively hyperventilating. Now imagine I do it just for a second. Less of an effect obviously. Or a thousandth of a second? Hell I could turn that air into laughing gas and if it was only for a thousandth of a second, it probably wouldn't affect you.
Point is that time is a factor.
How many people do 5:10 breathing?
I know divers that do 5:10 breathing for a minute or two before the dive, then claim they can resent the blood CO2 by, "throwing in a tidal breath to stop HV", (I've got that in writing from a qualified freediving teacher). But they won't do purge breaths because, "that's HV". Don't make the mistake of thinking HV = fast breathing.
You can do three purge breaths in maybe 5 seconds, and gas composition in the lungs only changes with the inhalation of the second one. If it takes about a minute for blood to circulate then AT MOST 10% of the blood is exposed to the mildly altered CO2 level in the lungs, and then only for a few seconds.
So yes that's HV but it's a TINY amount.
Whether that effect is offset by the benefits of purging is another question.
Personally I've moved away from purge breaths in favour of relinquishing all conscious control of the breath and focusing instead on relaxation and calming the mind.
Last edited:
VERY good post. Few divers understand that time is a major factor. Mild hyperventilation for a long time can be much more effective at reducing co2 levels(and a lot more dangerous) that fast and deep for a short period. It can be particularly dangerous because the diver doing mild HV for a long time doesn't usually know he is doing HV, much less understand the time issue.
Under breathing: Good observation, but its more complicated. For a while, I was intentionally under breathing. Combined with 3 purge breaths (about 25 seconds) it was very effective in half lung diving. After a while I got to the place where I could just relax and forget about my breathing(where I am now) In the last minute of so, I'm not trying to under breathe, just breathe as little as possible consistent with maximum relaxation and no urge to breathe. In good conditions, this results in very very little ventilation near the end and a very relaxed, near "meditative" state. Purge breathes following that are less than when I was intentionally under breathing.
There is a funny sort of balance(means I don't understand it well) between time, breath up ventilation, relaxation, and purge breathes. Get it wrong and I get a short dive. Get it right and I get a fleeting urge to breathe at about 30 seconds which goes away and I know I'm in for a long comfortable dive.
To the "stale air" issue. Purging to introduce as much fresh, low c02, hi O2 air into the lungs as possible effectively provides a much bigger space to offload co2 and stores more 02. I forget the numbers, but the amount of both in the lungs is significant to the length of a breath hold. You can easily see the difference on the couch with the difference in time to first contraction with full vs empty lungs.
Under breathing: Good observation, but its more complicated. For a while, I was intentionally under breathing. Combined with 3 purge breaths (about 25 seconds) it was very effective in half lung diving. After a while I got to the place where I could just relax and forget about my breathing(where I am now) In the last minute of so, I'm not trying to under breathe, just breathe as little as possible consistent with maximum relaxation and no urge to breathe. In good conditions, this results in very very little ventilation near the end and a very relaxed, near "meditative" state. Purge breathes following that are less than when I was intentionally under breathing.
There is a funny sort of balance(means I don't understand it well) between time, breath up ventilation, relaxation, and purge breathes. Get it wrong and I get a short dive. Get it right and I get a fleeting urge to breathe at about 30 seconds which goes away and I know I'm in for a long comfortable dive.
To the "stale air" issue. Purging to introduce as much fresh, low c02, hi O2 air into the lungs as possible effectively provides a much bigger space to offload co2 and stores more 02. I forget the numbers, but the amount of both in the lungs is significant to the length of a breath hold. You can easily see the difference on the couch with the difference in time to first contraction with full vs empty lungs.
Last edited:
Just had a quick look at this thread and haven't had time to really read up on the subject but one in your otherwise very good and detailed explanation I think you have to take the time perspective even further: If you change the gas composition in the lungs it will have an effect over time after the beginning of breathhold since more CO2 will travel to the lungs because of that, and therefore increase slower in the bloodstream during the next minutes. So yes, purge might not affect the bloodstream immediately, but it will over time I'd say. Alot I'd say.
A very observant observation. You are, of course, correct, but thats not the whole story. Siku made a good point with his simplified example. You make a different one, just as interesting. Since clearing the lungs of stale air provides a place of offload c02 out of the bloodstream, it effectively delays onset of DR, especially blood shift. Thats bad for safe diving, but it makes for more comfortable dives. Same as HV. One way its different, the lungs offer 02 storage, quite a lot, so that balances off at least some of the c02 storage. Not sure what the net effect is.
Last edited:
Agree - it's a very complex calculation. That's probably why we have to be pragmatic about it 
The safest might be to just stay away from hyperventilation/purge as a rule of thumb.
But if I don't hyperventilate/purge at all doing deep diving, my contractions start early at app. 20 m making it very difficult to keep mouthfill later on (but possible at times).
If I get more training time in deep waters I think I'll be abe to relax better and do 0% HV/purge.
So it also might vary with experience as mentioned before, but also current training form, especially also the mental side/relaxation.
The safest might be to just stay away from hyperventilation/purge as a rule of thumb.
But if I don't hyperventilate/purge at all doing deep diving, my contractions start early at app. 20 m making it very difficult to keep mouthfill later on (but possible at times).
If I get more training time in deep waters I think I'll be abe to relax better and do 0% HV/purge.
So it also might vary with experience as mentioned before, but also current training form, especially also the mental side/relaxation.
Here's what I heard from a real PRO freediver. Indirectly, through other contacts (someone I have contact with claims to have heard this firsthand from the freediver).
I don't know what his/her preparation is nowadays, but this is (so I heard) what the freediver once described as a routine for his/her static apnea:
Series of breathholds:
2 min. breathing, 2 min. static
3 min. breathing, 3 min. static
4 min. breathing, 4 min. static
then a 5 min. breathe up and max attempt.
As for the breathing, how it is done:
First part of the breathe up: inhale (belly only) 1 second, hold 2 seconds, breathe out 10 seconds, hold 2 seconds. Goal: relaxation.
Second part of the breathe up: for approximately 45 seconds: breathe in 1 second (full, two section breath: abdominal and chest!), breathe out forcefully 4-5 seconds (as if you are blowing up a balloon).
Thrid part of the breathe up: 10-15 seconds of normal, "passive" breathing.
...Then, breathe out (as much as possible) and then one last full inhalation...
The freediver who gave this info regularly goes beyond 5 min. ...easily.
If the first part of the breathe up isn't HV, the second part surely is, right?!
My contact claims the freediver who gave him this info is a real pro: he/she has been a member of the official U.S. team on world championships... I think this kind of breathing advice rather worrying... (I'm a total beginner by the way, having had a first AIDA initiation...)
Your thoughts?
I don't know what his/her preparation is nowadays, but this is (so I heard) what the freediver once described as a routine for his/her static apnea:
Series of breathholds:
2 min. breathing, 2 min. static
3 min. breathing, 3 min. static
4 min. breathing, 4 min. static
then a 5 min. breathe up and max attempt.
As for the breathing, how it is done:
First part of the breathe up: inhale (belly only) 1 second, hold 2 seconds, breathe out 10 seconds, hold 2 seconds. Goal: relaxation.
Second part of the breathe up: for approximately 45 seconds: breathe in 1 second (full, two section breath: abdominal and chest!), breathe out forcefully 4-5 seconds (as if you are blowing up a balloon).
Thrid part of the breathe up: 10-15 seconds of normal, "passive" breathing.
...Then, breathe out (as much as possible) and then one last full inhalation...
The freediver who gave this info regularly goes beyond 5 min. ...easily.
If the first part of the breathe up isn't HV, the second part surely is, right?!
My contact claims the freediver who gave him this info is a real pro: he/she has been a member of the official U.S. team on world championships... I think this kind of breathing advice rather worrying... (I'm a total beginner by the way, having had a first AIDA initiation...)
Your thoughts?
Interesting question
where is the boundary of HyperVentilation.
R deep breaths HV..
How about negative abdomen short breaths (skull shining) wich seems seems to relax &vitalise the diaphgram.
How ever the border between attempts to control breath thus risking the blackout or just diving &having diving limited by ability to hold breath is blurry &possibly circular.
To black out or to inhale water?
That may B the quesZioon..
where is the boundary of HyperVentilation.
R deep breaths HV..
How about negative abdomen short breaths (skull shining) wich seems seems to relax &vitalise the diaphgram.
How ever the border between attempts to control breath thus risking the blackout or just diving &having diving limited by ability to hold breath is blurry &possibly circular.
To black out or to inhale water?
That may B the quesZioon..
One of the multitudinous factors in this issue is what you are breathing up for. Different patterns almost certainly work better for different things. You "pro" friend is doing static in competition(surrounded by great safety), not my area. For serial diving in open water, his breathup would make me nervous. The HV portion of that breathup is a bit longer and much more aggressive than what I think would be safe. Also much more energetic, which wastes energy and acts against relaxation.
Just a caution, just because a diver is successful at competition, that does not mean that his technique is very safe.
Just a caution, just because a diver is successful at competition, that does not mean that his technique is very safe.
Assuming you mean approximately seconds and full breaths with minimal pause between, that's 4-5 full breaths per minute, when 1 per minute or a little less is resting ventilation rate. What do you think?
In the long run, you are better off, will get the same or longer breathhold, and be a lot safer, by limiting your HV to a small number of purge breaths(better none at all)forget about your breathing rate otherwise and focus instead on relaxing and doing other things that promote DR, like good technique, less than full inflation, getting your weighting right, etc.
I'm talking serial diving here. Dynamic and static are not my things.
In the long run, you are better off, will get the same or longer breathhold, and be a lot safer, by limiting your HV to a small number of purge breaths(better none at all)forget about your breathing rate otherwise and focus instead on relaxing and doing other things that promote DR, like good technique, less than full inflation, getting your weighting right, etc.
I'm talking serial diving here. Dynamic and static are not my things.
Last edited:
Breathing out longer than breathing in tends to slow down the heart; how much depends on how deep an inhale and how long a cycle. Make that 1/4 of a full inhale and 4:8 in seconds and most people in most conditions would not be hyperventilating, at least, not much. Make it a full breath and that is for sure HV. Keep doing that very long and (a) your heart won't slow down much and (b) you will blow off so much c02 as to be dangerous.
Ventilation: If you observe yourself in relaxed conditions (on the couch) you will find that you naturally take a relatively high number of shallow breaths, something like 1/10th of a full breath, 10 times a minute, or equivalent to roughly 1 full breath a minute(individuals will vary). Your resting breathing rate in the water will usually be slightly higher than that, depends on water temp and conditions. Breathups that result in ventilation rates much higher than resting rate, especially if they continue for very long, result in blowing off too much c02 and an unsafe situation. The 4:8 pattern can work, as long as it doesn't result in over-ventilation.
Ventilation: If you observe yourself in relaxed conditions (on the couch) you will find that you naturally take a relatively high number of shallow breaths, something like 1/10th of a full breath, 10 times a minute, or equivalent to roughly 1 full breath a minute(individuals will vary). Your resting breathing rate in the water will usually be slightly higher than that, depends on water temp and conditions. Breathups that result in ventilation rates much higher than resting rate, especially if they continue for very long, result in blowing off too much c02 and an unsafe situation. The 4:8 pattern can work, as long as it doesn't result in over-ventilation.
Last edited:
That is the safest. However, you will find that no HV at all, no purges, etc makes for a very short dive until you do the other things that lead to a strong early DR. The urge to cheat a bit is overpowering. What I have done is set a goal to minimize HV and work toward it over time. Suggestion: try forgetting your breathing for long enough to be fully rested and relaxed, then 3 purge breaths, then go. Work on all the other things that result in a fast DR. Over time you will find that you need less and less purges and your dives get longer and longer.
A simple way to find out if your breathup is hyperventilation is to check if it delays contractions compared to normal automatic breathing. From my experience I can tell that even 8s inhale/16s exhale breathing if done for ~3 minutes significantly delays contractions.
If you want to induces DR as early as possible you should get rid of all stuff that covers skin on your head (mask, goggles, nose clip, swimming cup etc.). Don't wet your face before a dive, it should be warm and dry. DR is strongest during the first dive, serial diving induces a warm up effect that delays DR initiation.
If you want to induces DR as early as possible you should get rid of all stuff that covers skin on your head (mask, goggles, nose clip, swimming cup etc.). Don't wet your face before a dive, it should be warm and dry. DR is strongest during the first dive, serial diving induces a warm up effect that delays DR initiation.
Last edited: