• 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!

Should I be accending before contractions start?

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
Jan 16, 2002
Practicing in my office, I dont mind pushing it some. I still havnt been able to hold off the extreme urge to breath for too long. I usually hit the urge and begin getting the throat contractions, and can hold out for only about 3o more seconds like on the first try.
My question is: Do you, or should I begin my accend before I get the strong 2 minute mark urge to breath with throat contractions, or should I be like 3/4's of the way up all ready? What do some of you more experienced divers do? I cant imagine being down in the 50 -70 ft range and holding off that urge, but if thats what i takes to stay down, then more training will have to commence. Thank You.
I'm in your same position and very interested in what that answer is to your question aswell.
Are having trouble finding a dive Buddy like I am?

I will stay down at depth for 20 contractions before ascending while rec diving, and more if my buddy can see me.
Erik Y.
I have never experienced any contractions on the descent only on the way to the surface maybe the last 25% of the ascent...I would push it more but defintely not without a buddy...and if you start to experience contractions at depth it's probably a good idea to take a good long break before your next dive...

David Lee
Jamaica W.I.
Welcome David!

For those of you who may not know, David Lee is a top level freediver who set the official Unassisted Constant Ballast world record to 147ft / 45m without the use of fins or any propulsion device. On October 21st, 2001 David then set a new world record in the unassisted constant ballast category to an amazing depth of -47m.

Welcome to the forums David!
Thanks Cliff,
Believe it or not I just discovered this forum not too long ago...nice to be able to chat with some other freedivers who aren't discussing freediving politics...this is a great way to kill some time while bored at work :)

Another unassiste cb record is in the making for July 12th to 50m back home...

Hope all is well,

Safe dive to all...

Jamaica W.I.

Hey Mark
Hope that I don't sound like a broken record (does anyone remember those things?) but, contractions are a very individual thing. I doubt that I'm the only one that doesn't have them at depth, so please go slow. I suspect that the urge to breathe is very reduced or absent below about 60 feet and if I ever have a contraction below the 40' marker, I'll drop the belt and grab the rope. Two weeks ago, on the worst dive ever, there were no contractions, urges to breathe or other warnings. Earlier this year, I spent three minutes at 50 feet with no urge to breathe. Felt like I could stay forever. NOT.
By the way, we have a small group that watches closely and they all dive deeper and longer than I. Makes me feel relatively safe.

Cripes... I get what I can only guess are contractions after about 45 seconds and they are distrubing enough that I haven't been able to stay down longer than ~1 minute. I think I need to do a lot of hangs at 10m just to get used to these.
About contractions...

Hello Mark9989 Et Al,

Dive within your comfort zone. If you aren't comfortable and relaxed then what's the point? You want to feel natural in the water, so just relax. Don't be in a hurry to expand your comfort zone either, just enjoy diving. You might try apnea walking as a training tool as well. Try to alternate evenly between breathing and apnea; When that 'panic' feeling starts to creep up during the breath-hold, just tell yourself to relax--everything’s normal. Most importantly, always err on the side of caution.

If you're diving alone, then a good 'rule of thumb' is to be surfacing just as you get the urge to breathe; controlling contractions won't extend your O2 supply and you can't afford to push the envelope. Here's a brief description of Shallow Water Blackout and what happens when we dive to -10m, though you're probably already familiar with the concept:

At sea level, the air you breathe is .21 ATA oxygen and .79 ATA nitrogen (plus some trace gasses). Our brains require a PaO2 of .10 ATA to remain conscious, so if we dive to -10m we might have, say a PaO2 of .42 ATA in our blood (because the atmospheric pressure doubles between 0-10m) giving us the impression that all's well. If we use 60% of that O2 while at depth, then as we ascend the partial pressure will decrease to ~ .09 ATA and we'll pass out, probably around -4 to -3m -- hence the term Shallow Water Blackout. If you hyperventilate then you're blowing off co2, which is what triggers you to breathe; this can give you the false impression that your O2 levels are higher than they are. This, in combination with the diving physics described above, is one reason why hyperventilation is so dangerous. It doesn't sound like you are hyperventilating, but the idea of controlling the urge to breathe is similar.

Here are a few suggestions if you must dive alone:

1) Always dive conservatively, I can't emphasize this enough.
2) Do not focus on a goal while diving as most people die from SWB because of this.
3) Limit your bottom times to 1:30
4) Always give yourself at least 1.5-2 times the dive time to recover, this allows your body to replenish O2 and out-gas co2 which will build up over time.
5) Limit your depth to -20m
6) Remain aware of and pay attention to your body; how do you feel? If you're not ‘in the groove’ then don't push it--go home and dive another day.

Obviously, as we become more comfortable under water, tolerant to co2, and our bottom time increases, the likely hood of a BO increases as well. If you can dive with a buddy, please do so. The caveat here is this: wearing a seatbelt does not make it safer to drive fast, so don't let your buddy give you a false sense of safety--they may not be able to rescue you.

Hope this helps, I sound like my parents! :hmm

Safe and happy diving,

Last edited:
Good advice in general however I disagree when people throw numbers around.

A bottom time of 1:30 may be nothing for some people, while others may be blacking out at this stage. I think I've seen this figure in the Terry Mas book, if that's where it comes from.

Same goes for the 20m depth.

Even with beginners there can be a huge difference in abillity. I've been training a friend, and under close supervision he has already done a 5:15 wet static, after only 2 weeks practise.

Now I've seen some other beginners, and most couldn't do more then 2 minutes.

I'm glad I didn't set any limits as far as time, otherwise I'd be holding my friend back. I confess I got a little nervous seeing him get such long times, but I knew he had done longer times with dry statics.

There are times when it's OK to push a little, ie a pool, buddy right next to the person, knows what to do etc. In fact I think this may even be safer as the person will then be less tempted to try out their abilities in a less safe environment.

Ultimately in comes down to your own judgement of how you feel,
and learning your bodies signals as you are running low on air.

Woops, didn't see that the comments for limiting depth & time refered to diving alone.

I still agree with my last post though. If you set any time & depth limits make them a lot less then what you know you can normally do.

Still much much much better to have a buddy, however I understand that sometimes the choice is to dive alone or not dive at all. I've done a lot of solo freediving, and done some silly things, and am just plain lucky I'm still here to write this post.
Now even though my abilities have improved a lot, I am actually more conservative then I used to be. When I have a buddy/ safety diver, that's when I know I can go a bit closer to the limits.

Just be very conservative, no room for mistakes !
Certainly reccomend coming up before contractions.

contractions....I get them after about 45sec when rec. diving.. I usually dive about 10 contractions when diving solo, even with buddy here where water is so dark that you are practically alone below 10m..
I would agree with bill contractions are very individual thing! I once did a little static..that I got first contractions around 1min but did bit over 4:00min...
I think it is one of the hardest things to judge..wether you are pushing it or not...even when you are being conservaative with your diving it might be close to you limits depending on many factors that affect your diving......:hmm self awareness!!
safe diving!
Numerology and freediving...

Hello Walrus,

The figure of 1:30 as a recommended maximum bottom time was taken from a medical report finding on SWB (from the 60's?). Same for the depth limit. Perhaps that is where Terry Maas got his information too. The gist of my entire post was to dive conservatively, know your limits, and enjoy diving (slanted mainly at the solo diver).


Last edited:
Excellent Answers Guys

With all the talk about contracions, I am now not even sure if I've reached them. All I know is that when that extreme urge to breath kicks in and my throat begins to suck in, iI begin to wonder if I should be just about to the surface, OR if I relax I still have a good amount of time or 02 left. Some post give the immpression that there is plenty more time if you can just get past that urge to breath. <~~~ Something I find hard to get past 50 ft down. I get affraid of BO. Thanks !!!
walrus do you know the song ridin solo? i heard you dived solo(dangerous but good time to ask this question). do they even play hiphop in australia? top 40?
now back on topic what i do(and not alone) is stay down for contractions as it is a bigger thrill the longer i am away from air.
Last edited:
i stayed down so long once to feel contractions that the person watching me refused to tell me how long. i am NOT kidding.
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.