Correct breathing pattern

[Blackwood]

Originally Posted by gnulab

Hi Blackwood, so at the exhale part, it should be continous instead of inserting pauses in between?

I don't know about should, but it certainly feels more natural.

My advice would be: don't actively try to control your breathing. Log some more time, and your consumption will most likely improve as your comfort in the water increases.

[Web Monkey]

Originally Posted by gnulab

thanks heaps guys!
one down, bouyancy to go!

Today is your lucky day!

Properly weighting yourself, then moving the weights/tank around until you're naturally horizontal will improve both your air consumption and your buoyancy.

This is because being overweighted means keeping a huge bubble of air in your BC, which expands and contracts like crazy as you ascend and descend, making controlling your buoyancy very difficult.

Any time spent getting yourself properly weighted and trimmed will pay you back every time you hit the water.

Enjoy!

Terry

[halemano]

Originally Posted by Blackwood

When I'm relaxed, it's something like a slow inhale (about 5-10 seconds), pause (about 1-5 seconds), slow/full exhale (about 10-15 seconds), pause (about 1-5 seconds), repeat.

I doubt the typical basic scuba diver even understands how impressive a breathing rate of less than 4 breaths per minute is, but I just have to say - very impressive. I know a petite instructor named Cindy that nears 4 bpm when relaxed and I thought she was suffering brain damage

[DA Aquamaster]

A couple more thoughts on breathing...

In general the breathing pattern should be the same as your normal breathing pattern with two exceptions. Inhale a bit deeper using the diaphragm more than the chest, and pause after the inhale, not the exhale.

It is VERY important to note that you hold air in during this pause with the diaphragm. If you instead close off your throat, you are holding your breath which is dangerous. The difference is by pausing and holding air in with the diaphragm, your air way is still fully open and any excess air volume created on an ascent woudl just vent out your throat and mouth with no lung injury occurring.

As CJM indicated, you also want to be sure you do not push it too far. What triggers the urge to breathe is the CO2 level, not the falling O2 level, so if you feel the urge to breathe - breathe. If you don't you end up building up more CO2 and then retain more of it. The elevated CO2 levels ill give you a headache, but more importantly make you much more susceptible to oxygen toxcity and nitrogen narcosis. Many divers who report the onset of nitrogen narcosis at shallower than normal depths are often divers who are "skip breathing" to try to reduce their gas consumption.

It gets really scary when those same skip breathing divers are technical divers who may operate at depth at PO2's around 1.4 and then decompress at a PO2 around 1.6. They are at elevated risk for ox tox and are most likely diving much more impaired due to the effects of nitrogen narcosis regardless of the equivalent nitrogen depth of the mix they are on. When I see divers coming out of caves with headaches from trying to extend their penetration before hitting thirds, I just shake my head. Diving in a cave with increased nitrogen narcosis due to elevated CO2 levels is just plain stupid.

[DA Aquamaster]

Originally Posted by halemano

I doubt the typical basic scuba diver even understands how impressive a breathing rate of less than 4 breaths per minute is, but I just have to say - very impressive. I know a petite instructor named Cindy that nears 4 bpm when relaxed and I thought she was suffering brain damage

No offense, but remarking that a respiration rate of only 4 breathes per minute is impressive creates the belief that such a low rate is desireable.

For someone who is very petite, very fit, with larger than average lung capacity for their size, doing basically nothing in the water, it may be fine. For the other 95% of the divers trying to achieve it, it is not for the reasons outlined in the post above.

Breathe normally or with the slight modifications given above and if your gas consumption requires more gas - get bigger tanks.

The biggest thing any diver can do to improve air consumption is to eliminate all extraneous movement in the water. Any muscle movement burns oxygen and creates CO2 so any arm waving or torso bending that is not required is wasting gas. Torso movement in particular is very innefficent as the muscles involved are very large, yet people never consider it. It is tension in the torso muscles in new divers who are not relaxed that accounts for much of the increased gas consumption. The ability to relax combined with less extraneous movement and improved trim in the water are what result in a new diver's SAC decreasing with experience.

A more efficient kick and better streamlining and trim to reduce drag in the water (reducing the need to kick as much) will greatly improve gas consmption as you reduce CO2 production and naturally reduce the urge to breathe and decrease your respiration rate.

If you look at the average rototilling feet down diver from the side, you will note that their frontal area is greatly increased compared to a diver who is perfectly horizontal in the water. The difference in area is as much as 4 times as great and when you consider that drag is a squared function, at the same speed, the rototilling diver with 4 times the frontal area is potentially working 16 times as hard as the properly trimmed diver - not even considering the less efficient downward thrust vector involved.

In short, improve gas consumption by relaxing, moving less and gliding longer between kicks due to better trim and streamlining rather than by intentionally trying to breathe less.

[Slonda828]

Originally Posted by Blackwood

When I'm relaxed, it's something like a slow inhale (about 5-10 seconds), pause (about 1-5 seconds), slow/full exhale (about 10-15 seconds), pause (about 1-5 seconds), repeat.

Naturally, breathing patterns reflect work load.

+1 for what blackwood said. This is exactly how I breath at a normal pace. The only time I really change this is if I'm working hard on something, or if I am doing things at a hover. There are times at a hover where I will pause my breathing to make sure I don't bump the bottom. If you search youtube for videos of divers hovering, you'll see that many use their breathing to stay still in the water column.

[ScubaSteve]

Originally Posted by DA Aquamaster

No offense, but remarking that a respiration rate of only 4 breathes per minute is impressive creates the belief that such a low rate is desireable......

Thank you DA. What people seem to be getting caught up on is timing your breaths. You can't do this and offer it as advice. Every single person is different so if the OP (or anyone else) follows this to the T, then they are putting themselves at risk. Maybe it will be right for them. Maybe it won't. What is wrong with this:

Breathe Normally as you would anywhere else only through a piece you put in your mouth. Do not try to copy others....be yourself. Your SAC will improve but by copying others, your SAC may never get the chance to improve.

[TSandM]

Let's think about breathing for a minute. Your body structure involved in breathing consists of your mouth/nose, your trachea, your major bronchi, and eventually the bronchioles and alveoli. None of the first several structures participates in any gas exchange. So, when you breathe in, a certain amount of the breath you take ends up sitting in those structures, doing you very little good. When you exhale, you exhale that volume "unused", as it were. So, say your normal breath, sitting in front of your computer, is about 500 ccs (as could be possible). Say 100 ccs of that breath is sitting in the dead space. That means 20% of the gas you're moving in a minute is "wasted". Now, a normal person, sitting still, is probably breathing 12 to 16 times a minute, so they're moving, say 6 liters of gas a minute. They need that to keep their CO2 normal.
They're exhaling 1200 ccs of "unused" gas per minute, then.

Now, imagine the anxious, stressed new diver. He may only be taking 300 cc breaths, so he needs to take more like 20 of them per minute. That means he's wasting 2 liters of gas into the water per minute!

Now, imagine that you increase the volume of each breath to 1 liter. You now need only six breaths per minute to get your 6 liters. 100 ccs is still going to be held in the dead space with each breath, but this is now 10% of the gas you're moving. You're going to waste 600 ccs, instead of 1200 ccs, in each minute. You've gotten more efficient!

This is why a slower and deeper breathing pattern than what you use at your computer is recommended for diving. It makes more efficient use of the gas in your tank. The problem comes in when somebody deliberately tries to slow their breathing down to where they are no longer moving that required 6 liter of air per minute. Then the carbon dioxide level in the blood goes up, leading to breathlessness, anxiety, increased narcosis, and post dive headaches and nausea. This is the reason people caution so strongly not to focus overly on breathing by itself. As long as you aren't "panting" (rapid, shallow and inefficient breaths, typical of anxious people), you are probably doing just fine.

Overall gas consumption is best addressed as DA Aquamaster wrote -- by increasing efficiency, streamlining, and relaxation.

(Note: I know the math above is inaccurate, because I haven't accounted for the fact that it's ALVEOLAR ventilation that needs to be kept constant, rather than total minute ventilation. I did that to keep it simple.)

[halemano]

Originally Posted by DA Aquamaster

No offense, but remarking that a respiration rate of only 4 breathes per minute is impressive creates the belief that such a low rate is desireable.

I once had a bar manager who worked with an egg timer. He would go into his office and set it for an hour. When it went off he would come out and tell the bartender "no sarcasm!" I was that bartender

My post was a sarcastic BS call, intended to stimulate conversation about the improbability of the breathing pattern quoted.

If you look at the times in the paren's, one breath every 17 seconds is his fastest breathing rate; adding the minimums together. On the slow end of his spectrum one breath takes 35 seconds.

I personally tell my students the book is wrong (PADI OW) and that deep breaths are not the best way to dive. IMHO, ~2/3rds full is what I teach because when you go beyond that I feel you have to flex chest muscles to expand the rib cage, thus creating more CO2 and using more O2, diminishing returns and causing you to be less relaxed. The deeper breaths also cause more buoyancy swing, especially when pausing for "(1-5 sec)" at both empty and full.

If you start with the mind set that you will take normal relaxed breaths, the brain will adjust naturally to the ventilation requirements of the moment. The only pattern I mention is exhale twice as long as you inhale and inhale slowly; I would be impressed with a beginner having an ~9 sec cycle (3 sec in, 6 sec out), which would be ~7 breaths per minute.

The instructor I mentioned in my previous post (Cindy) typically breaths in for 5 sec and out for 10 sec, but she has well over 10,000 dives and weighs just over 100 lbs. She lasts longer on a tank than all but two of the thousands of divers I have been in the water with (both female, similar size, similar experience, similar consumption).

Thinking about relaxing the entire upper body (gently hold wrist), attaining a hydrodynamic streamlined body position (head slightly lower than feet) and finning properly (toes pointed, move from the hip, water pressure bends the knee slightly, not the brain bending the knee); that's how I encourage divers to get better on their air.

[DA Aquamaster]

Originally Posted by Slonda828

There are times at a hover where I will pause my breathing to make sure I don't bump the bottom. If you search youtube for videos of divers hovering, you'll see that many use their breathing to stay still in the water column.

Sometimes it involves a choice - I will alter my breathing patternfor the purpose of buoyancy control, as changing lung volume with just the right amount of lead time is a great way to start or stop a change in depth or to hold perfectly neutral. Of course, too much of it begins to impact the sac rate, so its a tradeoff. so consequently, I try to limit the percentage of time I have to spend holding an exact depth during a dive.