hypothermia thoughts

[Tong]

Hi all,

I was sat down thinking about hypothermia and freediving the other day and i had a thought!! rofl

If you could lower your core tempreture before you got into the water could you increasr your bottom times dramaticly??

the thought behind it is that when you start getting hypothermia your body starts routing blood to the vital organs, so by being mildy suffering hypothermia you wouldnt be wasting precuious O2 on bodily functions that you dont need when diving.


any thoughts??

 

[Chrillepille]

Well, if you lower your core temperature you start to shake because the muscles contract to produce heat (and thus using oxygen) - bad idea.

If you lower your core temperature so much that the shaking stops your bottom time will probably be very long, since you will not be able to get up by your own and drown - bad idea.

[ame=http://en.wikipedia.org/wiki/Hypothermia]Hypothermia - Wikipedia, the free encyclopedia[/ame]

 

[trux]

You may be interested in this thread: http://forums.deeperblue.com/freediving-science/74458-stop-shivering-get-cold-especially-naiad.html

However, although there may be benefits, getting voluntarily hypothermic prior the dive may be rather risky, so do not take that study on seals too seriously, and better avoid risking your health and life. Hypothermia may be life threatening, and when exercising apnea, the temperature may drop quickly below safe limits. So, cold freediving may have advantages, but should not be done without proper preparation, long training, and good supervision.

 

[TRITON]

From my experience to get the strongest dive reflex you should be cold but not shivering as it increases O2 consumption.In addition to that i've noticed that the majority of my good performances in Dyn and dnf i've done in pools with lower water temperature.

 

[Mullins]

I always assumed that too, because I get noticeably more vasoconstriction in cold pools and feel subjectively like I have more of a DR. But then, I found long distances no harder in the very warm pool in Sharm, which was odd. And the NZ pool in which I seem to perform best is also the warmest (only by a degree or two). It does have other advantages though, like more consistent depth.

 

[Drejcha]

Hypothermia slows down you metabolism which is good to some deegree, I think. Especially for those who have difficulties calming themselves just "with mind".
My pb's were always made in rather warm conditions, though. It seems to me I'm loosing much less energy because body doesn't waste it for warming up.

What about the danger of missing the warning signs leading to BO in cold enviroment? Isn't there a problem of just slipping away?

 

[Jon]

There may be some advantage to one-off competitive events that I'm not aware of, but for my normal diving, which is almost always in cold/ice water, I find that my bottoms times get drastically shorter the colder I get. Once the shivering starts (first sign of hypothermia) my bottom times start to fall apart.


Jon

 

[efattah]

If you can inhibit shivering and lower your core temperature, your apnea will increase dramatically. The problem then, is how to prevent or delay the shivering. There are numerous approaches including cold tolerance training, marathon running, as well as foods/herbs.

 

[Tong]

the reason i started thinking about it was because i dive in a 543 surfing suit i get old alot sooner than my spearing bud's but my times increase as the dive goes on, i may start working on my "cold tolerance"

i am imaging the scene from cool runnings right now if only i had dredlocks!

 

[xristos]

Hypothermia slows down you metabolism which is good to some deegree, I think. Especially for those who have difficulties calming themselves just "with mind".
My pb's were always made in rather warm conditions, though. It seems to me I'm loosing much less energy because body doesn't waste it for warming up.

What about the danger of missing the warning signs leading to BO in cold enviroment? Isn't there a problem of just slipping away?

After I start shivering freediving performance drops off sharply for me.

I had misunderstood all this written here some years ago and thought cold increased performance. Had an LMC and then another one. Usually I get hypoxic-light headed if I push too long not LMC?!

COLD IS DANGEROUS and yes @Drejcha I think you are right you can easily slip away.
@trux sums it nicely.

 

[elisecoen]

Basically, your body wants to keep it's temperature up. It needs to stay above 95 F to survive. As it falls below there, your limbs become non-essential, only the heart and brain and organs matter, if they can't stay warm, you die.

In water, it's incredibly dangerous. Water is very conductive and can kill a healthy person in minutes in 60 degree temperature. Generally it takes freezing temperatures to bring on hypothermia, but infirm people, especially the elderly could die of hypothermia at room temperature if the body is unable to maintain at least 95 degrees F (preferably 98.5).

When it is below freezing, your cells and tissues can freeze (we're mostly water held together by lipids) this is known as frostbite.

For whatever reason, your brain requires you to be above 95 degrees. Your cognitive abilities drop off and you experience amnesia when you get down to 91 degrees, and you can lose consciousness at 88. Your brain contains most of the glycogen in your body. I don't know if it's the cause of the temperature or the result of having the energy. The chemical processes can't function properly when the go below that level. And it requires a tremendous amount of energy to keep everything going.

 

[johnvictor]

Experienced mild-moderate hypothermia last year in Squamish, BC while hiking the Stawamus Chief. It was pouring rain and about 50 degrees when we began the hike. I was woefully under-geared, and just decided to push through the misery with a cheap rainjacket, a pair of shorts, and hiking boots. It was chilly to start, but I'd done hikes in the cold before, and figured I'd just get warm after a few minutes. Body temperature did equalize after about fifteen minutes, so my friend and I pushed on. At the top we decided to climb the ferrata up to the top of the Chief (a very inadvisable decision in a downpour), which only made things worse The granite was incredibly cold, and by this point I was completely drenched. Parts of the hike had streams of incredibly cold water dumping over me.

 

[HLanger1955]

Hypothermia is reported to save lives in extreme conditions, for instance people ending up in the sea after ship wrecking. Body functions are then heavilly reduced wich helps to avoid brain damage. In freediving I guess we should not go that far. Finally, when we feel cold ourbody starts to tremble in order to keep temperature at a high performance level...