• 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!

dry-packing sambas and blackouts

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.

bevan dewar

Well-Known Member
Sep 26, 2001
while packing before doing pack-stretches i sometimes get samba-like shakes and recently woke up on my floor with a lump on my head. anyone know what caused this blackout? cant be low o2 levels so i'm figuring it must be due to pressure disrupting bloodflow? this cant be healthy can it? cheers
You did too much too soon...

I have never blacked out from lung packing to date - and that is with as many as 60 gulps of air.

I do all my packing in a yoga Lotus position and do it at a slow rate.

Sounds like you may have dropped your blood pressure too low from the increase in pressure on the heart from over packing...

:naughty Please be careful and do your packing in stages to adapt your body to the technique...

I started out doing 20 packs, then 30, then 40... I am now up to 60 - I have done 75, but it was more effort as opposed to the possibility of blacking out.
Yes, that must have been something with the blood pressure.
I made some experiments:

my normal BP was 119/84 at a heart-rate of 64.

then I packed my lungs and held my breath during the measuring:

BP dropped to 95/55 :duh, while the heart-rate rose to 90:hmm

I got extremely light-headed, my ears felt hot like hell.
I always get these symptoms while packing dry.
I guess the high pressure inside the lung leads to compression of the capillaries, thus creating a high pressure inside the lung artery, and a low pressure inside the lung vene which brings the blood to the left atrium of the heart.
The heart fights against the high pressure of the lung artery, trying to pump blood into the lung, the heart-rate rises.
Due to the low pressure of the lung vene, there's not enough blood being pumped through the aorta into the body, the blood pressure drops.
Try packing in the water and watch for similar symptoms.
I never had these symptoms while packing in the water.
I will make the following experiment:
pack my lungs and hold my face in cold water - i guess the diving reflex prevents the symptoms. BP and heart rate should stay normal.:cool:
Speaking of packing...

I don't mean to change the direction of this thread, but this subject of packing is of interest to me. Never having performed this yet, I am curious to know how much time each pack increases bottom time, and more importantly, how much time is spent packing the extra. Maybe I'm seeing this incorrectly, but it would seem the time spent packing the extra air, is burning some time from the initial inhale. Does this practice make significant improvements? If so, I would like to try it.


JJ, I can't give you exact numbers, but can assure you that with experience, packing will increase breath-hold times at the surface and in a dive. Packing also lets you dive deeper, by giving you more air for equalising.
Once you learn to pack quickly and have significantly stretched lungs, the time and effort spent will be outweighed by longer holds.
If you start blacking out during packing, then stop for a few seconds until your head clears, then resume. That's usually enough to get past it.
I'd like to acknowledge that a great deal of information I have has been obtained through discussion with Eric F, especially packing and recovery techniques. Thanks Eric.
Erik Y.
Last edited:
Number of packs

When I hear people say that they pack up to 60 times, I fear it may be misleading for many newcomers to freediving.

The point of packing is gradually increasing lung volume and using your cheeks and tongue to 'pack' air into your lungs that your diaphagm can't possibly do on its own. So perhaps those who find they pack 60 times, don't inhale a large quantity of air to start with.

Packing efficiently is most important.

This weekend was my first day of diving for the year. Out of curiosity, I tested my lung volume with a spirometer first without packing: 6.78L. Then with packing, it took about 18 packs and I got 8.11L, then an hour later, just before diving I did another packing test and got 8.43L.

Pretty normal numbers: about a liter and a half increase in volume in about ten seconds. But after 5 months of inactivity, I was happy to see that my lung volume was the same as it was when I was actively freediving last year.

Of course the other use of packing is to stretch the lungs and prepare them for pressure at depth. I suppose if I tried adding on packs to my max, I could over time nudge my lung volume up a bit, but there is a physical limit to how much air you can get in. (The size of your rib cage and your lung tissue) For me, my max is just under 9L (so far 8.81L). So the energy required to eke out that last half a liter isn't worth it for me.

So to answer advice about packing and light-headedness:

Some people have low blood pressure to start with and can rarely pack without a black out.

For the benefits of lung stretching, do it lying down and pack slowly as Cliff does. You should have time to feel your vision tunnelling in as your bp drops. Always exhale slowly to avoid a rapid pressure change, even when you feel fine.

If you black out when lying down, perhaps a doctor can give you valuable information about your blood pressure.

Focus not on the number of packs, but on the sensation. And if you have a spirometer, you can see how efficient you are.

When I started freediving, my lung capacity was about 5.7L. Since then, through packing and reducing residual volume, it's much higher. Which always helps. :)

The debate over the time spent packing is worth it is a long one, but many freedivers find that packing is the difference between 30m and 50m+. Mostly for equalizing reasons. That's been my experience, anyway.

lung capacity

Hi Pete
Bet it's good to get back in the water. Some of us trained all winter, so you have a little catching up to do. Welcome back. It sounds like the water was clearer in Vancouver than Hawaii this weekend but I don't want to trade away my 26 degrees.
I'm not familiar with a spirometer and the only one I could 'play' with will cost me as much as a new D3 (no brainer). Do you know exactly what it measures and how?


The spirometer measures the flow rate of air through it and the total air expired. It's a medical device (one of Eric F.'s many) that costs $300-400 I think. Less on ebay.

Send some warm water our way... :)

I should clarify my original post...

Beings that I only started lung packing in late October of last year when I attended Kirks clinic, I felt it necesssary to try and see where I stood in my lung capacity. Needless to say, I may have given an incorrect impression about the number of packs one should do in order to be successful.

Since I view freediving as a personal sport, all that I do in my training is vital for my own feelings about how well I should be doing.

I realistically only do 2 - 3 sets of packing, starting at 20 and working up to 40 max.

I apologize if I gave the wrong impression on this topic...
I have blacked out due to packing luckily I was on the side of the pool, so only got a big bump on my head:duh I don't know why this happens, I'm writing this just to say that it has happened to someone else.

For me it has been due to less than 10 packs, though it has only happened dry, so far, sometimes it doesn't happen:confused:

So your not the only one to find a bump on your head after packing:D

How to dry-pack?

Hi to everyone,
After reading this whole packing stuff, I am wondering how to do dry-packing step by step. I do not get what is meant by the term "packing". Is it an advanced technique that the newbies shall not use? Is there also wet-packing?
thanks and Sorry for my ignorance:confused:
Don't worry arbat, all are learning, you can read a great explanation about packing wrote by Eric Fattah at
To learn more about it's applications, try a search in this forum.

I believe all the bad symptoms are related with the intrathoracic pressure.
When you do a packing, you increase the intrathoracic pressure, with that increase the venous return to right and left ventricles are less than usual and the cardiac output can go very low (syncope-black-out).
It's very difficult to find the "rigth" pack for everyone, but after a dry black-out you will now how far to go.
I agree if a person has a low arterial pressure, can be more prone to a black-out with this technique.
As in many of the things, the common sense will guide you
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.