Gasp Response

A couple of times when we dumped our canoe, my wife experienced the gasp response. Never heard of it until recently when reading the posts about paddling in cold weather. The first time it happened we were in Florida and it wasn’t cold! The other time it was a rainy day in the summer and cool. I did the swim both times and didn’t have a problem. My question is what is the best strategy for preventing it happening since she seems to prone to suffer it even when the conditions aren’t extreme?

Here is a great source of information

– Last Updated: Nov-06-04 2:30 PM EST –

Yes, I was surprised too when I got Wilderness First Responder training and we experienced this first hand. Many factors, besides how cold the water is, although the colder the water the more serious and involuntary the gasping. Some people can start gasping in 80 degree water(supposedly chills us same as 42 degree air).

Most important protocol we learned was to cover all areas where blood is at surface and least fat and where receptors are located to trigger this, head, neck, keep water out of nose, armpits, groin, feet, hands. Prewetting neck occasionally, may somewhat increase tolerance if thrown over, as will keeping as much of you out of water as possible until gasp reduces. Keep mouth above water immediately, get out asap.

An insidious cause of this can be preloading, that is, chronic cold challenge, by evaporation, not eating enough, fatigue, over time, so that when hit water, have little resistance. (Being no expert, more complex stuff beyond my training).

Here is a really great site with the principles and suggestions for dealing with it.

many ways
More stable boat, more practice in the boat, weigh the boat down, etc etc

There is evidence for gender differences

– Last Updated: Nov-06-04 1:37 PM EST –

I looked up reference for my training and here is excerpt about generalized differences and why they exist. Sorry, does not offer concrete remedies, but does offer clues about being more cautious.

Data suggest that women exhibit a more rapid
drop in core temperature than men when immersed
in cold water.This increased rate of core tem-
perature fall is present if both genders are matched
for body fat content. Increased body fat in women
does provide insulation during water immersion;
however, the larger surface area-to-mass ratio and
the lower thermal mass contributing to heat pro-
duction will result in women’s faster initial cool-
ing rate during water immersion, compared with
that of men.

As mentioned earlier, exercise during cold wa-
ter immersion may produce sufficient heat to re-
tard the drop in core temperature. For men and
women of the same body fat composition, decreases
in core temperature are greater for women in the
resting state or when performing light exercise;
however, with more intense exercise, women main-
tain a higher core temperature than men.

If men
and women exercise at the same absolute work in-
tensity, there is no difference in cooling rate.
Under these conditions the women are exercising
at a higher percentage of their maximal aerobic
power and are therefore producing a greater
amount of heat per unit thermal mass. Women ex-
ercising at the same percentage of their maximal
aerobic power as men will cool at a faster rate, illustrating the imbalance between heat loss and pro-

I don’t think the initial gasp response

– Last Updated: Nov-06-04 2:40 PM EST –

has a lot to do with cooling of core temperature ... it is an instantaneous reflex response to being hit with cold liquid, not enough time for significant cooling except at the surface of the body. Areas effected are the face and neck and chest especially. You can train yourself to resist gasping to some extent. A lot of us here kayak surf in cold water (some a lot colder than others :) ) and many of us wet our faces and clothing before paddling out into cold waves. If it is really cold (55F) I stick my head underwater several times before paddling out. I believe Sanjay posted quite a bit on this quite some time ago. Someone said the gasp response maximizes at 59 F, that seems too warm for me. I do know if the water is cold enough I will gasp. You can build up your tolerance just by turning the shower on as cold as it will go and stepping in. add buckets of icewater to really get a good effect (Check witth your cardiologist first though). This June my son and I made a bet that we would swim in the North Sea. It was way too cold and stormy but our last night in Denmark the waves calmed down and so our host took us down to the coast. My son is a much better swimmer/surfer than me and without his wetsuit he had a severe attack of the gasp response; it really surprised him, the water was about 52 F, we have surfed together in water that cold but prepared a bit first.

yep, vey much mostly response to cold on skin, sorry, if not real clear, just wanted to show some of the other smaller factors.

Main deal does seem to be body kicking in from nerve responses.

It stimulates body to produce more energy, respiratory hyerventilaion results in

growing inability to hold breath, dyspnoea, inability to coordinate breathing, cardiovascular increase blood pressure, workload, tachycardia arrhythmias, noradrenaline and adrenaline producing intense panic.

up to a point, really agree, fitness level, habituation, and knowing what it is all about provides some reduced effect and better handling of it. Still a big big problem is that the seriousness of it can vary widely from time to time, same conditions same person, so no one can really count on knowing how they will respond completley. Prevention better.

try a
internet search. Some helpful tips for this are given. Also knowing is half the battle.

This info appears to be carefully
assembled. What puzzles me is that I can’t mesh it with my whitewater paddling experience. I have flipped, wet-exited, and taken substantial swims in sub 55, even sub 45, and in some cases my state of dress was less than ideal. And I have successfully rolled in water that was quite cold (Tellico in February). I did not take in water involuntarily, and I did not experience hyperventilation.

Something psychologists learned while studying “involuntary” reflexes is that even though they might not be subject to voluntary inhibition, they may not occur under different starting conditions. There may be something about the state and behavior of a whitewater paddler that greatly diminishes the impact of sudden immersion of the face and neck.

In my teens, I used to have to “open” a cold swimming pool every spring, by diving to the bottom (no wet suit, no dry suit) and removing plugs from the plumbing. This was in Chicago in late March, and the pool was probably no warmer than 45-50 degrees, since it had been surface-insulated with foam slabs and a cover. I experienced no gasp, no involuntary water intake, and not much in the way of heavy breathing afterward, although I always incurred first degree hypothermia, and spent 40 minutes shivering in a warm bed.

Last Winter’s Surf Session
I got sucked out of the boat. I didn’t have a gasp reflex, likely because I was well dressed for it, had on two hoods and wet my exposed face before heading into the surf.

I was at an outer break and got repeated cycled in the plunging waves, at times right onto the ocean bottom. While I was warmed and dry in my drysuit, the 34 degree water did seep into my hood and I was getting a severe ice cream headache. My breathing became very accelerated, far more than the effort I was putting out to swim since I was very conscious of staying relaxed and not fighting the waves.

I swam again last month in upper 50 degree water, in similar surf conditions. My breathing was no where near the accelerated levels I had experienced at the winter session. In restrospect, I am pretty convinced that the cold water at the winter seesion was affecting my breathing and that if it had taken me longer to get out of the water I would probably have started hyperventilating.

My preventive measure this year for winters surfing is to get a thicker and tigher surf hood.


Experiencing it sheds new light…
Had it happen to me when paddlin’ the Sturgeon River with a group of people in mid-October. They had had snow up there the week prior so you can imagine how cold that bath was. I think it was caused by quite a few factors: 1)extreme surprise and shock- first time I had ever been caught by an eddy and dumped 2) Water was over my head and I was temporarily jammed under the boat next to a log( nice goose egg on head to prove it!) 3)I totally believe in theory of losing core heat quickly- since I have gotten in shape and lost a lot of excess weight, I get chilled very easy these days- The wet suit helped quite a bit. 4) Inexperience!!!

That river was too challenging for me for the conditions and weather. I dumped again at the end of the three hour tour and It was not as traumatic and I did not gasp for air- did a lot of grumbling and cussing though. All I can say is that If you are not certain of your capabilities on a higher class river, check it out in warmer weather or scout it out ahead of time and have lots of extra clothes, Hey Northman, can I borrow those wool pants again some time? Longshadow seemed to think they were pretty sexy!)

I learned my limits this year in paddling. The 20+ mile trip on a slow moving river was the bomb! But those short torrential rivers where you can’t enjoy the scenery are not my cup of tea. Not to mention the Dr visits afterwards are a bit pricey!

After that trip I thought I was done until spring… It is supposed to be in the 50’s and sunny today. Think we will dropped the 'lil ones off with granparents and hit some water- Damn addicting!

Be careful out there people!




Cold Water Immersion: It’s More Than Just Hypothermia!

Background: The Seventeenth Coast Guard District Boating Safety Alert program provides timely information of “Lessons Learned” from non-

commercial boating casualties.


Review of the past 3 years of boating fatalities in Alaska indicate that approximately 75% of the individuals who died probably succumbed

to initial stages of cold water immersion, rather than actual hypothermia. In 44 of the 58 fatalities, victims either never surfaced or did not make it to shore, and probably died well before any actual drop in their core temperature. We all know the adage “cold water kills.” We used to lump it all into “hypothermia.”

The reality, though, is that cold water immersion follows 4 stages, starting with “cold shock,” followed by “swimming failure,”

then “hypothermia,” and finally “post-rescue collapse.” You need to know how your body will react to cold water immersion, so you can

take appropriate action and increase your chance of survival!

Lessons Learned:

  1. The initial cold shock from falling into cold water provokes an immediate gasp reflex, of up to 2-3 quarts of air - or water, if your

    head is submerged. If you inhale water, it is highly unlikely you will come to the surface unless you are wearing a lifejacket. This

    means you have to have your lifejacket on when you enter the water!

    The cold shock stage is characterized by hyperventilation and rapid

    heart rate, which often produce a panic feeling. This stage lasts 3-5 minutes. The initial shock can also provoke a heart attack, which

    will make self-rescue extremely difficult. During this period, concentrate on staying afloat with your head above water while you

    adjust to the shock so you can act more effectively.
  2. Next, swimming failure sets in after 3-30 minutes of immersion. If you have made the decision to swim to shore without a flotation aid, you are not likely to make it. Tests using Olympic swimmers graphically show how your body progressively becomes more vertical in

    the water due to loss of muscle coordination. You will be unable to make forward progress and keep your head above water when this

    occurs. Having a lifejacket on at this stage is essential to survival so that your head does not slip below the surface of the water during

    efforts to rescue yourself or be rescued.
  3. True hypothermia sets in after at least 30 minutes in the water, depending upon water temperature, body type, size, insulation of

    clothing, acclimatization, and other factors. This means that if you have a lifejacket on, you have a significant “window of opportunity”

    for survival.
  4. Once rescued, someone who has been immersed in cold water is still in danger from post-rescue collapse, as blood pressure drops, inhaled water can damage the lungs, and heart problems can develop as cold

    blood from extremities is released into the body core. It is vital to treat the victim gently and get immediate medical care.
  5. What is the key here? WEAR A LIFEJACKET at all times when boating!! This keeps your head above water if you suddenly fall

    overboard or capsize, and gives you those precious minutes you need to get back onboard. Even if you have a lifejacket in your hands, you

    may not be able to put it on. If you cannot self-rescue, it may give you some hypothermia protection and can extend the time you can

    survive until someone else can rescue you

Sanjay’s Pith Post…
I found it after a bit of searching…

very informative as usual …

The both times it happened
we were close to shore and spent only a minute or so in the water. Both times the water was cool/cold but not frigid – don’t know the temperature. The second time it happened we were taking a whitewater class. It was cold and rainy and we were dressed for the weather with Gore-Tex and fleece. We had a rental whitewater boat for the class and we dumped it shortly after the put-in in an eddy. It was a complete surprise. Maybe that was the key factor: complete surprise? When we dumped in Florida we were pinned on a log in a spring-fed stream and dumped trying to push off. We don’t do any extreme paddling but like to go tripping up in Canada. It would be simpler if we paddled whitewater when you expect to get wet and dress for the swim, but we don’t do that kind of paddling. The two times we dumped were the only times we ever dumped since we started paddling three years or so ago. The good thing about all the discussion about winter paddling was that it started us thinking more about the swim. The danger for our type of paddling is that is easy to forget about the cold water you’re paddling on when you don’t expect to go swimming. Thinking that a semi-dry top would work for her since it would keep most of the water out till she gets to shore? How about some head gear?

seems to be the question here. When we did water survival in the Navy they taught us to place our chin against our chest when entering the water. Part of what kills people in the gasp response is that their chin dops and with their mouth open they suck in huge quantities of cold water. Part of thhis response is triggered by cold water hittine the base of the skull and also getting into the ears and destabilizing the body’s mechanism to maintain orientation.

So, keep the back of the neck warm or at least insulated, petroleum jelly works well. Keep water out of the ears, ear plugs as already advised. And yes, aclimatize. Or better yet go south go someplace warm to paddle. I live in Pennsylvania and just wait for spring.

Keep on paddling,


The narliest thing is LOC!
My Wilderness Medical Doc Trainer putting us through a simulation reminded us that the worst aspects of Cold Shock is LOC, sudden loss of consciousness, from hyperventilation (causes arterial hypocapnia, which leads to decreased brain blood flow and oxygen supply. This may lead to disorientation, loss of consciousness and drowning.) and sudden death can occur either immediately or within a matter of minutes after immersion (i.e., due to syncope or convulsions leading to drowning, vagal arrest of the heart, and ventricular fibrillation).

Neither of these is something that we will have any ability to deal with once unprotected and in the water. Plus, there is less predictability than we think, one can be fine for years and have different response even if acclimated and mentally prepared.

We were taught to not depend on any one technique and to not get confident. The best way to deal with it as many have said here is to reduce the areas of the skin that are exposed and to slow the cooling of those areas.

Or as the previous person said so well if this is just too much of a hassle for only so much fun wait for the warmer water.

I use 100% silicone grease on my neck area to reduce irritation from latex gasket but have begun applying to the face when the water is cold. Have found that it takes the sting off cold water. My pores are effectively sealed.


I think it varies widely

– Last Updated: Nov-12-04 10:04 AM EST –

I have a sort of delayed gasp reflex, and only when cold water gets into my sinuses. A flip and roll in really cold water (40s-50s) does nothing to me pretty much. If I hang out long enough and don't have enough coverage on my head, I might get an icecream headache, but that's about it.

But a missed roll in cold water results in some involuntary gaspy/gaggy breathing and burping for a few seconds, once I've finally rolled up. I'm guessing that's a result of the cold water flooding my sinuses, since the only time I get water up my nose on a flip is if I blow my first roll attempt. Even then, I can control the reflex until I'm upright.

Of course, whitewater paddlers probably aren't good benchmarks for analyzing this. The sport pretty much self selects for people whose bodies deal well with sudden immersion.

I read that
there is no danger of hypothermia in florida waters. What about gasp reflex?

Gasp Reflex…
You can get a gasp reflex in your own home in the shower even. The nature of an involuntary response is that it can occur almost anytime for almost any reason. Going from cold to hot will often also trigger a gasp reflex. However there are a number of things you can do. As mentioned above proper clothing can go a long way but just proper clothing isn’t enough! If nothing else your face is still exposed and we are talking about an involuntary response. So what to do? Desensitize your body to the gasp reflex. What do I mean? Get in! Spend some time under controlled settings going from hot to cold and cold to hot. Many divers as well as extreme groups like the Polar Bear clubs practice getting these involuntary responses under control. Much like you would practice a roll or a brace practice getting the involuntary response under control.

Breathing is also an involuntary response but with practice you can supress your bodies need to breath for periods of time - freedivers do it all the time. Panic is also an involuntary response one that often gets you into more trouble than necessary. Actually just about any involuntary response can be desensitized but it takes time and practice. One last one, your heart beat is an involuntary response but it is well documented that free divers as well as many others are capable of slowing down their heart rate when necessary.

Much like anything else practice, practice, practice.


You might get hypothermia in Florida?

– Last Updated: Nov-08-04 3:59 PM EST –

Looked up lowest water temps in Pensacola, 55F in Janurary and in Key West, 69F.

Hypothermia can occur in water much much warmer than we think. It is surprising but 80F water is similar to 42F air in cooling effect. The definition of cold water is variable. The temperature of thermally neutral water, in which heat loss balances heat production for a nude subject at rest (i.e., not shivering), is approximately 91-95F. Hypothermia eventually results from immersion in water below this temperature. For practical purposes, significant risk of immersion hypothermia usually begins in water colder than 77° F. Using 77° F as the definition of cold water, the risk of immersion hypothermia in North America is nearly universal during most of the year. Add to this the degree of cold challenge from wind, waves, food intake, dehydration, exhaustion, thin or fat, body type, have to swim, lack of clothing, etc..

Cold shock comes from rapid cooling of skin and how extensive an area, so possible, just guessing that you could get it if got really overheated, skin tempurature way up, and sudden whole body thrown into water. Less likely for sure, possible maybe.