Slower breathing rate underwater?

[RJP]

One goal of diving is to acquire a slower breathing rate while underwater.

When you first learned to dive you probably had a higher rate of breathing because you may have been anxious and a little stressed during your beginning dives. Over time you develop a calmer attitude and more comfort in the water, resulting in slower breathing.

By having a slower breathing rate, you will be able to maximize your time underwater by extending the amount of time you can get out of a single tank (or whatever your tank configuration).

As long as you are not holding your breath or skip breathing, you are fine. Your body will let you know if you need to breath faster. Enjoy the extra efficiency.

You're close... but you sort of have it 180 degrees out of phase.

A slower breathing rate is - for the most part - a desirable state for scuba divers. However, it is not a "goal" of diving. In fact it should be noted that breathing rate is only one part of the respiratory equation that determines air consumption. The other part is the depth (volume) per breath. A slower breathing rate that is shallow may result in CO2 buildup and/or simply not deliver sufficient O2 to meet the metabolic needs of your body. Neither of these two situations are desirable.

Air (O2) consumption is a DEMAND function which is controlled by the metabolic needs of your body in terms of delivering O2 to your body's cells and removing CO2 that results from metabolic processes. Accordingly, the best approach to reduce air consumption is to reduce your body's DEMAND for O2 delivery and CO2 elimination. There are 13 key "Demand Reduction Strategies" that any and every diver can employ to improve their O₂ consumption:

1. Slow down
2. Get more comfortable in the water
3. Slow down
4. Get your weighting fine-tuned
5. Slow down
6. Get your horizontal trim dialed-in
7. Slow down some more
8. Stop swimming with your hands and arms
9. Slow down even more
10. Utilize efficient propulsion techniques
11. Just a little bit slower... please?
12. Streamline your gear
13. Slow down - you're still moving too fast!

Reducing various behaviors, factors, and circumstances that increase your body's metabolic processes - which increases the DEMAND for O2-in/CO2-out - is an appropriate goal. Achieving this goal will result in a decreased respiratory rate and therefor decreased consumption. I know it sounds semantic, but I've found that most students/divers have better results when they get the cause-effect relationship down. Doing so will allow the diver to identify and correct the underlying cause of an elevated respiration rate.

Two fine points to add:

1. Sometimes - especially with new divers - an elevated respiration rate is a reaction to anxiety, etc. And yes, that underlying cause should be identified and addressed as well. (See point number 2 above.)
2. Within about 10 seconds someone will reply to this post saying "But breathing exercises and yoga-type techniques are shown to reduce anxiety and slow the body's metabolic rate, etc, etc." Fine. However, that's not really any different than what I'm suggesting: the goal is to identify the cause of the elevated breathing rate and addressing THAT. Doing so will result in a reduced breathing rate and improved gas consumption. But I will suggest that - other than in anxiety/panic situations - divers should implement (and probably exhaust) the various DEMAND reduction strategies as the primary focus.

 

[yaronad]

You're close... but you sort of have it 180 degrees out of phase.

A slower breathing rate is - for the most part - a desirable state for scuba divers. However, it is not a "goal" of diving. In fact it should be noted that breathing rate is only one part of the respiratory equation that determines air consumption. The other part is the depth (volume) per breath. A slower breathing rate that is shallow may result in CO2 buildup and/or simply not deliver sufficient O2 to meet the metabolic needs of your body. Neither of these two situations are desirable.

Air (O2) consumption is a DEMAND function which is controlled by the metabolic needs of your body in terms of delivering O2 to your body's cells and removing CO2 that results from metabolic processes. Accordingly, the best approach to reduce air consumption is to reduce your body's DEMAND for O2 delivery and CO2 elimination. There are 13 key "Demand Reduction Strategies" that any and every diver can employ to improve their O₂ consumption:

1. Slow down
2. Get more comfortable in the water
3. Slow down
4. Get your weighting fine-tuned
5. Slow down
6. Get your horizontal trim dialed-in
7. Slow down some more
8. Stop swimming with your hands and arms
9. Slow down even more
10. Utilize efficient propulsion techniques
11. Just a little bit slower... please?
12. Streamline your gear
13. Slow down - you're still moving too fast!

Reducing various behaviors, factors, and circumstances that increase your body's metabolic processes - which increases the DEMAND for O2-in/CO2-out - is an appropriate goal. Achieving this goal will result in a decreased respiratory rate and therefor decreased consumption. I know it sounds semantic, but I've found that most students/divers have better results when they get the cause-effect relationship down. Doing so will allow the diver to identify and correct the underlying cause of an elevated respiration rate.

Two fine points to add:

1. Sometimes - especially with new divers - an elevated respiration rate is a reaction to anxiety, etc. And yes, that underlying cause should be identified and addressed as well. (See point number 2 above.)
2. Within about 10 seconds someone will reply to this post saying "But breathing exercises and yoga-type techniques are shown to reduce anxiety and slow the body's metabolic rate, etc, etc." Fine. However, that's not really any different than what I'm suggesting: the goal is to identify the cause of the elevated breathing rate and addressing THAT. Doing so will result in a reduced breathing rate and improved gas consumption. But I will suggest that - other than in anxiety/panic situations - divers should implement (and probably exhaust) the various DEMAND reduction strategies as the primary focus.

All of this is really great " game plan " and advice - really
I can say that I was investigating the issue from all the angels......and of course improved all the necessary / must / common....etc.


All that = took me from "not acceptable" Air consumption rate"....to "ok"
I was aiming to very very good breathing and air consumption rate.


And the only advise from a "5000 dives ( special forces) diver" that really helped was:


1. like in marathon running = there is a point that the body has to get used and change / improve....
it is right after you think in your mind that you know what you are doing.....and actually switch into "calm mode".....
and actually it is "out of you hands"! The more you dive the fast you get there


2. another good tip ( not easy ) is to try breathing between the "trim points" .....take the "air IN" ,
just to the point that you start floating up.....and OUT just to the point you start sinking down


......Good Luck!

 

[bowlofpetunias]

I really find I am entertained by people going on about air consumption. Some are just more efficient. It usually improves with diving as techniques improve. Some even have good consumption rates right from the get go in spite of their stress levels

IMHO the issue comes down to basic rules.

The rule that rules all others ANYBODY can call the dive at ANY TIME for ANY REASON with NO Questions asked and NO flack afterwards.

1) Am I fit emotionally and physically to do this dive?

2) Do I have a well thought out dive plan?

3) Have I planned adequately for the Gas required?

4) They make tanks in all sizes.. get the right one for your air consumption. Tank size and low gas consumption do NOT define the diver! I know great divers with high consumption rates and terrible divers with excellent consumption rates!

5) The dive turns based on the person with the lowest gas levels no questions no recriminations no teasing and no guilt.. it could be you next time.

It seems to me that the more people fuss and worry about their breathing rate the worse it is and the less they enjoy the dive.

 

[DiverRtNY]

Math time to play off of shallow breathing at an average rate compared to deep breathing at a slow rate:
Average dead space ventilation (air movement that isn't part of gas exchange) with our anatomy is 150ml (average for sake of argument) Add on 30ml for the second stage ( guestimate, not actual)and lets play off of 180mls for deadspace ventilation total.
Average tidal volume of a normal breathe is 500ml (just taking an average, everyone is different).
Take 18 breathes a minute. That is 9 Liters we breathe a minute with 3.24 liters being dead space ventilation to equal 5.76 liters a minute of gas exchange.
Now lets take some slow breathes of 800 ml at a rate of 10. Dead space is the same because that's a constant per individual and we get 8 liters a minute we breathe and 1.8 liters being deadspace with 6.2 liters being of gas exchange.
You blow off more co2 with less gas consumption when doing slow deep breathes.

 

[dumpsterDiver]

I don't really understand your math, but I agree with your conclusion..

 

[LandonL]

You're close... but you sort of have it 180 degrees out of phase.

Out of curiosity, how exactly do I have it out of phase?

I was just giving a light explanation in layman terms without going into full med school physiology mode since we are in the 'basic' forum. I could of course pull out the book and give the process a breakdown to a molecular level. I am currently reviewing for my licensing exam anyway, it would be good practice. lol.

You definitely stated it more eloquently, but I don't particularly see anything I stated that was wrong or 'out of phase'. While typing I was thinking goal wasn't the right word, so 'desirable state' does seem to fit better. Just seems like we are nit-picking the semantics. Whichever way you chose to define it, for several aspects of diving it is desirable and a benefit.

While depth does effect air consumption, I was speaking in general terms, as in if you were to conduct the same dive at a higher breathing rate, your air consumption would be higher. In general a slower rate of breathing will improve air consumption for the same dive if depth, pressure, tidal volume, time, BMR, alveolar gas exchange rate, work load, and every other detail is accounted for... which can be stated in simplistic terms as the same person doing the exact same dive.

With the information about not breathing shallow, good addition, I had assumed it was known to take full breaths. This method has of course kept (most) individuals alive thus far at the surface, but put someone in scuba gear and they can often surprise you.

I thought I had accounted for this with the bit about skip breathing and holding your breath, because if you are breathing shallower while taking longer breaths, the airflow rate would be so low you are essentially holding your breath or skip breathing. Your body would be screaming at you to breathe more as CO2 retention increased. Common sense should account for this scenario, but you are correct, for a beginner it may not. Had I witnessed something like this with a student I definitely would have addressed the issue, on a message board I just didn't take that into account.

 

[Iralub]

Thanks for the info everyone. I won't pretend to have followed the air volume calculations , but it is good to know that I'm not doing anything weird or harmful by breathing much slower than normal (I'm not actually trying to, it seems to just happen).

 

[Rick Murchison]

I find that my breating is generally slower and deeper (by about half and double, respectively) when diving, particularly if I'm maintaining neutral buoyancy on open circuit SCUBA. For me I think it's as much of a "proper timing and gas volume vs specific gravity and vertical stability - that is 'inhale at the rate to prevent a sink and then exhale at the rate to prevent a rise' - to maintain steady buoyancy" than anything else. If I'm resting on a ledge doing a long deco I tend to breathe a bit more like I'm out of the water, though still somewhat deeper and slower.

Rick

 

[FishLovingStudent]

A good part of this phenomenon you mention is an evolutionary trait called "the mammalian dive reflex." A reflex built to help us gill-less mammals survive our encounters with water. The slower circulation and heart rate it causes contributes to the slowing of your breathing rate underwater.

Another factor that I would guess is that we are weightless underwater, reducing the physical exertion needed by many muscles needed normally on land to support structure.

Mammalian diving reflex - Wikipedia, the free encyclopedia

I was editing some underwater videos that I took, where I could hear my breathing, and noticed something that struck me as strange - I seem to be breathing much slower underwater than usually

I counted myself taking somewhere between 5 and 6 breaths a minute (including when finning along), which is about half what I do sitting here typing on the computer. It seems a bit strange that I'd be breathing slower during activity underwater than I do while at rest now.

Is that a normal thing or should I be breathing at my usual rate? I'm definitely not holding my breath, but my inhales and exhales seem to be a lot deeper under water.

 

[GrandpaScuba]

It's called the Mammalian Diving Reflex and it is real. Scientific studies have shown that it is real. When water hits the face, it triggers a reflex that slows the breathing.