• 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!

Convulsions

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.

uberman

Member
Jun 18, 2010
51
2
18
Last week I was doing dry statics at my computer. The max for this series of 8 breath holds was 4:00 minutes, which I had done before in a pool. This time, however, I 'packed' my lungs with around 5 xtra sips of air just before breath hold #6....
I remember trying to get up off the floor but my head kept banging into the bottom of my bedframe, as my bed is next to my computer. When it stopped, I calmly thought to myself that I had just had a convulsion. I was not tierd, droopy, foggy or anything other than feeling normal. I check the time and found I had went down in less than 10 seconds into the hold.
Now, a week later I did the same series of 8 and again convulsed. This time my wife saw it. She said my head was banging over and over again into the keyboard. I came out of it fine again but a little spooked.
I did do about 7-10 very deep breaths just before the holds with no problems until around series #5 or 6. My time between holds starts at 2:00 and then decreases by 10 seconds while the breath holds start at around 1:30/40/50 and increase by 10 seconds.
I would like some feedback. I spearfish at least 1x week on average but am rarely under for more than a minute and am in about 20-30 ft of water on average (weighted to float up from 30' in unconcious).
Never had this happen before. Until I understand it better, I will not be doing any deep hyperventalations over 4 deeps breaths before a dive. In fact, I am going to start training to slow the heart to where I only need 4 breaths/minute, taking a deep breath just before going under.
Thoughts? Also, anyone had a simular experiance and could packing be part of the issue here, as that is the only variable that was different in these two cases.
 
You may get better advice in another part of the forum, but I would go see a doctor.

Was the second episode only a few seconds into the breath hold as well?
 
I was in my 5th breath hold period, about 10 seconds in when it happened. I believe it was the combonation of 1. Hyperventilation in the last 20 secs before starting this breathold, and 2. The packing expanded by lungs causing them to push into my heart a bit, resulting in reduced bloodflow/02 to my brain. The two things in tandem spelled 'whiteout, or convulsions.' Since I had done many many Apnea C02 tables in the past with mild hyperventalation with no ill results, it was only when I added Packing into the mix that this occured-BOTH times I did it.
 
ChrisMar replied to your other thread - definitely avoid packing and HV but maybe also have a checkup just in case. I saw a similar thing happen when we were kids and some were trying to artificial induce a BO by pressing against the chest of someone holding their breath. Usually they just BO'd and came round quickly but one kid went into convulsions and it actually took him a while to come back - really scary!!!

I am guessing that these convulsions were an LMC but not sure why it took so long for him to come round.
Posted via Mobile Device
 
Remember that there are many other factors that influence a person's susceptibility to BO and convulsions. Your level of fatigue, whether or not you have eaten, overall neurologic health, pH and other factors. Some people can become more susceptible if a given set of circumstances occur. Low-fat diets can even make one more prone to convulsions in some cases. High fat diets have been used to treat seizure disorders when medications do not work. The nervous system depends a great deal on fats/oils; healthy ones help it, bad ones don't and no fats at all is very bad.
 
  • Like
Reactions: trux
Thanks for the info. I generally eat very low-fat, so I should be taking a Omega 3 substitute I suppose. However, my convulsions only happened 2 x, both of which involved 3 things: More than 3 hours since I ate, 2. Moderate hyperventilation while getting ready for a breath-hold while doing a 4 minute Apnea Training Table, and 3. I Packed around 7 xtra breaths. I had done the first two many many times for training with zero convulsions. It was only when I packed that I convulsed. I did blood work the next day and found my Thyroid was low (I take thyroid medication-150mcg/day). I have been doing dry apenea training since without incidence. I dropped out all hyperventilation in favor of relaxation and a lung fill just over 3/4 full. Anyways, this week I get back into the water but to say I am feeling cautious is an understatement. I just dont want to ever be underwater and have an event like a convulsion.
 
Make sure you have a competent buddy and needless to say no HV or packing. Start with very easy dives to build back confidence - you'll have some additional stress as a result of the BO so it's impoRtant to go really easy and of course (always) have a buddy...

Don't let this stop you from enjoying Freediving - enjoyment and relaxation are key!
Posted via Mobile Device
 
I believe the BO is due to preassure on the hart from packing. I often feel very dizzy when I pack out of the water, but I usually spot the symptomes before it leeds to a BO. I`ve notised that it happens only when my body is warmer than normal. For instance when Im packing in the shower. Dont ask me why I do that :)

Dive safe
 
Why the heck are you hyperventilating?

Hyperventilation can lead to a black out with no previous warnings, and ALSO it can shorten your breath hold. It can increase your heart rate, make your blood alkaline (witch makes the bond between heamaglobin and the oxygen to strong, and the oxygen will not release properly to your brain, also called the Bore effect).

Packing could have something to with the problem to. When you pack, your lungs can actually compress the blood vessels going to your brain, causing a obstruction in the blood flow to your brain, causing a BO or LMC. When you pack immersed in water, the negative pressure will compress the size of your lungs quite fast and thus reducing the pressure from your chest.

My guess, a LMC (Loss of motor control) caused by hyperventilation (Because you hyperventilated you did not get any warning signs before).

A safer progress to longer apnea times would be to train to tolerate high CO2 levels.
 
Last edited:
Sunki-Thanks for the info as there was some things (negative pressure in water and the Bore Effect) that I had never heard of despite much research.

I do train to tolerate high CO2. In addition, I stopped the hyperventalition and concentrate on relaxation and slowing the heart, but that can be counter intuitive when spearfishing when you have to to 30+ dives as your moving alot. What I do is try to slow my breathing to no more than 4 breaths a minute before a dive. Then I sometimes take four deep breaths expelling all the air on the 4th one using my diaphram and then taking in a slow, deep breath and begin the descent. Its good to know that a couple packs wont hurt when I am in the water as it buys me a little more time underwater. Thanks again.
 
No problems, it is all knowledge that is taught in both AIDA and SSI courses. I recommend you to take a course, it is really good for developing not only your physical skills but also to build up your knowledge to safe and efficient freediving.

Was a little tired when i wrote it, it is of course not negative pressure in the water, the pressure arises and is compressing your chest, that is why you safely can pack and dive, but go easy, increase packing in small steps.

In the AIDA 4 star course it is also taught a lung stretching method that will help you with your packing abilities.

With regards
Bjorn
 
Im taking the Performance Freediving Intermediate class in Vancouver, Canada this Sept. Again, thanks for the info. I just wish there were other freedivers here on the Olympic Peninsula in Washington State. I dive on average 2x a week, 12 months out of the year come hell or high water. Water temps drop to 44 degrees in the winter and 48 in the summer. Tommorrow am going out spearing for Halibut. Other than me, theres a couple scuba guys who spear but other than that I am it unless some folks come over from Seattle. Cheers and happy diving!
 
DeeperBlue.com - The Worlds Largest Community Dedicated To Freediving, Scuba Diving and Spearfishing

ABOUT US

ISSN 1469-865X | Copyright © 1996 - 2025 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.

ADVERT