• 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!

Breath Ups On Quick Interval Dynamics

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
Sep 12, 2003
When I train with my buddies from underwater hockey, we do dynamics on a quick interval, like 25 meter underwaters on a 30 sec interval. This usually gives me about 8-10 secs on the wall for breath up. I have tried various combinations of long slow breaths to keep the heart rate slow, and quick purges to blow off the CO2. The problem with the long slow breaths is that I may only get one before the next 25. So, the question I have is: does one long slow breath replenish the O2 as much as several quicks ones? Does anyone have suggestions on how to best handle the breath up in between quick interval dynamics?

Not that I know the answer, but I would say, quick, deep, breath ups for these reasons.

1.) From many experiments with a pulse/oxymeter I have discovered that it really takes some hard, deep, breathing to replenish the O2 after breathholding. If I just relax and don’t get on top of the breathing, my O2% can drop a full 12% points before it will start to rise again. There just isn’t time in quick intervals to allow this to happen. If I get on it, it will usually only drop 4% points, before it rises.

2.) Deep breaths are important because the lower part of lungs have most alveoli and can do the most gas exchange. Make sure your belly is moving out on exhales and in on inhales.

3.) The early black out from hyperventilate because of low CO2 just isn’t going to happen, because you don’t have time to get your CO2 that low.

4.) Your body will adjust. Heart rate lowering for slow O2 consumption isn’t that important, because you’re only holding your breath for about 16 seconds. It’s okay to burn some O2 as long as you can get it back before your next dive.

5.) You need lots of air going in and coming out in the short time you have to get CO2 down to manageable levels.

6.) I believe I read it only takes ¼ of a second for alveoli to absorb O2 and expel CO2.

Just my opinion.
Last edited:

Thanks for the suggestion. I tried that out last night and it had HUGE effect. Usually, I start getting contractions around the seventh length. But, with the quick purges, I did twelve without one contraction. I also began slowly exhaling about halfway through each length. I wonder, though, whether exhaling during the dynamic is not bad strategy in the long run, because while it reduces the CO2- perhaps it also reduces the O2 because you are exhaling O2 that your body could otherwise absorb. Do you think that your body naturally expells the CO2 first, while retaining the O2?

Anyway, thanks again for the suggestion. I would like to get a pulse oximeter, because my guess is that I terminate my statics due to CO2 build-up rather than O2 depletion. Have you found that the two are unrelated, so that a person might experience heavy contractions from CO2, but still be within decent range on the O2 saturation?
I’m glad you were able to improve. I think you would probably lose some O2 by starting your exhale ½ way. Although CO2 is a concern in dynamics, blackouts (which are frequent) happen from low O2 not high CO2. So even though it may be painful, people are still reaching very low O2 levels.

I don’t know, but I think that with repetitive laps, with such short recoveries, you may not be getting fully oxygenated and the likelihood of blackout would increase as the number of laps increased. If this was to ever happen, you would be relying on your buddies who are probably tired and at the ends of the pool, to rescue you. Personally I would put up with a little more CO2 and keep my O2 as high as possible.

I think exhaling before you come up, so your first breath is all inhale, is a good idea. It probably decreases the time before new O2 reaches your brain by 2 seconds. It’s also like adding 2 seconds to your recover, which in your case is about a 14% increase.

I have definitely found that pain level and O2% are not that closely related. I think owning or having access to a pulse/oximeter is a big advantage, because you find out what your true O2 limits are and what it takes to get there.

I’m jealous of your access to underwater hockey. I wish it were available here.
Good luck,
Hi Dolphin Gang,
WaterRat here. I'm completely unfamiliar with underwater hockey, except I've had it recommended a couple of times to keep in shape. I've never seen it played, I'm not totally sure what all it involves.
I just like slow, relaxed Dynamics. No performance pressure. No WR chasing. I also like my Statics the same way.
I'm not a Comp diver. Rec is my style.

I do love my little experiments, done purely for fun.
Like: Focus on a certain Number of minutes during the entire Static. See how close I come.
Like: Go down and just let my mind wander. Examine the nicks in the swimming pool walls. Right before surfacing, guess how long I was down.
First experiment: I focused on 3 minutes. Got 3 minutes.
Second experiment: I guessed 2 minutes. Got 4 minutes.

Of course it's the coolest when I play Humpback Whale Song in my mind while doing whatever. That's when the dolphins come around. Sometimes it seems they're really there.
Oh yeah!!! MY BREATHE-UP! A few long, slow, breaths and down. I like relaxed.
WaterRat (Not that 17-year-old kid whose life goal was to beat Robert L. Foster and enter Guinness. I've had 30 years to think about it!....Prefer the WR on page 426, 1976 Issue. I've often wondered what Robert L. Foster thinks of the Freedive World now!)
I do quick deep breaths if I am doing short intervals. I don't know if this is the best way, but it has worked so far.

As always, it is VERY important to have a buddy with you at all times, even if the distances are short, because the short intervals can cause a cumulative lack of O2.


Here are some tips from my training where I do 2x25m (50m total) on 90 second intervals sometimes continuously for 1 hour:

-Safety is very very important.
-Belly breathing is key. I find it more effecient to breathe with belly only and keep my upper chest flat/deflated for gas exchange and do full chest expansion only for last inhale breath.
-Try to avoid really fast "panic breaths" right on exiting the water, try to immediately start controlled belly breathing which I find more efficient. These belly breaths can be quick though so don't try to make them slow.
-Try to do the quick purge breaths to dump C02 right on exiting water and then switch to slower breaths as you are done with breatheup (kind of hard with 8 sec breatheup though you may do this abit)
-Do "mouth breathing" where you exhale air into and out of your mouth and mask while doing the lap, you will feel and taste the old air from the bottom of your lungs mixing with the fresh air in your throat. Some people say this has no affect though my experience says that it helps and this is my theory why in 3 ways, 1 is to let you use more 02 while doing dynamic, 2 is to limit contractions as this "false breathing" "calms" the urge to have contractions and 3 is that it mixes the air in your lungs so when you exit to breathe you are exhaling more Co2 on first exhale breathe so helps to recover faster for next lap.
- When you are doing the interval breathing in between laps shape your mouth so that it has the least resistance to the air going in and out and also has the least volume. So you would open your mouth like an "O" and lift your tounge up somewhat along the back of the throat. This lower volume inside your mouth and lets the fresh and stale air inhale and exhale further/deeper so better air exchange.
- Focus more on full exhale then full inhale, this more efficiently/quickly provides air exchange then trying to do really big full inhales. Cheers Wes
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.