Cold Water Habituation

HABITUATION was one of my very first posts, and the first post I wrote about cold and cold water swimming, over four years ago, little realising it would become my favourite subject. Although it is linked in the Cold Water Articles Index, I decided to air it out and rewrite it. (And change those capitals).

Back then I mentioned how I  had progressed in cold. I used myself as an example to demonstrate progressive cold water ability. I was previously a surfer, wearing wetsuits year round and thinking I knew what real cold was. I later realised I had only ever once been close to getting as cold as I regularly get as an open water swimmer after 30 or 40 minutes. I had been surfing for six hours straight with no hood in winter that time.

 I started swimming open water during summer, but wore a wet-suit for the first winter for very irregular swims, and I was still surfing regularly. Toward the end of my second winter of swimming, which wasn’t as regular as I swim now, I decided to do my first non-wet-suit swim of the year, which was in late March I think, only a month after what is usually the lowest temperature of the winter here. March is still very cold water. 

Ballydowane Cove across to St. John's island

Ballydowane Cove across to St. John’s island

I clearly recall, will never forget in fact, arriving at Ballydowane Cove on a cold Sunday morning, with chest high waves, and feel physical effects of profound apprehension, even fear.

I recall that first experience of 7 or 8 degree water like it was yesterday, and I swam for 10 minutes. Disappearing in the waves, and ending up swimming the short length of the beach, and taking ten minutes to so do, and having warned her I’d only be in for a few minutes, Dee thought I’d been drowned. It seems a long time ago. The fear lasted for the next few swims before it disappeared.

The process of getting inured to getting into cold water is called Habituation.

It is not special, it’s not a reflection of an innate ability to handle cold. it doesn’t mean or signify anything. It’s a purely physical response and almost everyone can do it. (Excluding people with cardiac problems or certain circulatory or cardio-respiratory illness or other underlying contra-indicated health issues).

It will hurt for a few seconds or even a few minutes. Increased adrenaline beforehand may elevate your heart rate before you get in the water. You will find it difficult to breathe the first minute or so. You may flail about for the first one hundred metres. You can just relax and float in the water, you don’t have to swim. In fact that’s what King of the Channel Kevin Murphy prefers to do in cold water.

But, you will also settle and relax and get used to it.

coldI know it won’t kill me.

This is a primary mistake that some people make. They think that other swimmers, (more capable or tougher swimmers than them, in their mind), don’t feel it. They do. I do. It just matters less. Of course I also feel the same about other’s swimmers capability. Somewhere is a swimmer who really is better at cold than everyone. It make be Finbarr Hedderman. Or Kevin. Or Fergal, or Lisa or Alison or someone else. But we are all on the same spectrum of tolerance, just in different locations.

When I wrote this in 2010, I’d just met cold water Sandycove legend and Channel swimmer Finbarr the previous weekend, river swimming in Fermoy in 7½º Celcius (45½F) water, in October. At the time of writing, I wrote that seemed too cold for me as a sudden transition  from sea swimming in 10º Celcius. And I had a few years of cold water swimming behind me already.

It made me feel like he’s good at cold and I’m not. But Finbarr is much taller than I, meaning an overall greater heat retention.  He is also exceptional in his ability. He swam 35 minutes in that temperature. I was seriously impressed. I’m sure it hurt him too though, just as much as a 10ºC (50F) hurt me then.

Finbarr's smile here belies the fact that his foot is planted on Liam Maher's neck underwater.

Finbarr’s smile here belies the fact that his foot is planted on Liam Maher’s neck. Underwater.

In 2013/2014, I don’t consider that exceptional, and regularly swim the same or longer in that temperature. Of course Finbarr is swimming an hour.

The first few times you immerse yourself in very cold water will provoke a fight-or-flight response, elevating heart rate and stress hormones, potentially leading to anxiety or even fear.

I saw this with a friend recently when we were going for a swim at around 7.5º C. He hadn’t been in cold water for a couple of months so he was very anxious beforehand. He was utterly fine during his swim and afterwards.

Habituation just means becoming accustomed. In our case become accustomed to getting in cold water. It only takes four to six repetitions before the pre-swim anxiety abates and your heart rate to stay controlled. It become easier. The pain of immersion will decrease, though never disappear, and cold shock response will also reduce somewhat. Indeed there are few physical activities from which we can have such a speedy response.

More importantly, is you will realise that it’s not going to kill you. All the pre-swim anxiety will start to diminish. That the pain is not what you anticipated, that your imagination is worse than the reality. That every time you experience that initial response, you are reducing the power that cold may have over you.

You will start to see Cold in a different way, as a more intangible ghost over which you also have power. Until you too are part of this cult.


25 thoughts on “Cold Water Habituation

  1. HI Donal, have you come across Wim Hof and his unique breathing exercises/cold exposure routine by any chance? Still trying to figure out if these breathing exercises are worth the effort. He says it lowers pH in the body and so makes you more tolerant to the cold.


    • Hi Dewey, Yes I’m aware of Win Hof. I don’t find any value in him for cold water swimming, I don’t know any cold water swimmers who d, though there may be many.

      From what little of taken notice of Hof, I haven’t seeing him swimming, just sitting in stationary cold water and movement through cold water or cold air is different as heat is moved away from the body more quickly and micro-layers of warmer air or water can’t develop on the skin.

      I have not come across (or heard of) any reference previously to a correlation between pH and cold tolerance, but IANAD of course, though I’ve a bit on reading of the very specific subject of cold adaptation. On a very peremptory search, I can’t see anything, but search is always hard when no specific reference is available.

      All that said, I did hear an allegation from a very experienced cold water swimmer who I would listen to, that two people had died last year in applying Wim Hof techniques in very cold water, but other than location, I don’t know any specific details. – Donal


      • Hi Donal, do you see any other potential benefits of breathing exercises unrelated to cold water swimming as regards breath control, increased lung capacity. etc? A lot of swimmers seem to be playing around with various breathing methods nowadays to boost performance.


        • Hey Dewey, well breath control has long been a part of swim training, though I don’t really do it myself anymore (it does carry some risks, should never be done when alone). Specifically for open water, the advantage I see to doing some of it is to be able to tolerate rough water conditions better. Short-period cross-shore conditions are frequently challenging for people but I almost never swallow water, and I find occasionally in such conditions I may find that a wave unexpectedly might break just as I am about to breathe, so I delay the breath for one to three strokes. That may just be though that I now have so many years of experience of bad conditions that I just more comfortable and not fighting to breath. But I do see some swimmers, who are very strong, but don’t have the same experience are frequently accidentally swallowing water in bad conditions. – Donal


  2. I live in Austin, Texas and am lucky enough to have two spring fed pools to swim in that are fed by spring water that is 68 degrees (20 Celsius). For the last year and a half I have been regularly swimming 30 to 75 minutes (1 mile to 2.5 miles) two to three times a week with no wetsuit. I am trying to build up my tolerance to be able to swim longer distances. My core remains warm, but my fingers and toes begin to go numb (toes don’t go as numb as fingers). I still have good energy and swim strength and want to keep swimming but I’m wondering if this is dangerous? Should I stop when my hands go numb or can I keep swimming? Also, any suggestions on keeping my hands from going numb?

    I never experience shivering or any other symptoms after swimming and I warm up pretty fast after a warm shower. I am female, 5’6″ tall, 120 pounds.


    • Hi Francine. If you are not shivering afterwards I wouldn’t be concerned. Even in summer here (<16/17C) I notice that my fingers go white very quickly after being immersed but that has no bearing on my ability to keep swimming. It's only when you get The Claw that you are getting a real indicator that you need to consider exiting. But it’s sometimes possible to swim through The Claw also with training. Fingers aren’t related to core temperature, which is what you need to be careful of. Hope this helps


      • Thank you so much! I’m happy I can continues swimming after finger numbness. Never heard of the claw but saw your other posts in it and it was useful info. I’m so happy to have found a resource for questions like this.


  3. Donal, thanks for sharing. Lot’s of helpful info here. I’m training for Ice Swim (1K) in Dublin at the end of Jan. I’m up at around 750M at the moment. Water temp around 9C, I think. Not finding it too hard to endure the swim, but the more I gradually increase the distance, the more shivery I seem to get afterwards and it takes a bit longer to get back to normal. Having a hot shower afterwards helps … I’ve noticed that it’s warming me up outside, but inside seems to take a bit longer to warm up. Tried hat and gloves after swim today, but didn’t seem to make much difference. I guess it just takes a while regardless.
    Best regards,


    • hey Niall, a hot shower afterwards is a bad idea and should always be avoided, causing as it can too precipitous a core temperature drop. Lots of layers and careful walking is the best way to rewarm. My advice is to avoid Ice Kilometres and Miles all together, as they are stupid dangerous nonsense, and not pursued at all by the countries with the most extreme cold water swimming cultures and experience.


  4. Hi. I’m been trying to get used to cold water gradually by taking cold showers. It has taken me a month but I can now reasonably comfortably take a cold shower in water that is 8 C for five minutes. Do you consider this good preparation for winter swimming? I live in southern Canada where the lakes get very cold.


  5. Hello. My brother is an ENT surgeon. I used to swim in a pool when it got cold (though in texas) during the winter. It was deepTexas, so it was about 10 degrees celsius. My brother told me that you get bony growths in your ears if you continue to swim in very cold water. Have you heard of this (so to speak)?


    • It kind of is and isn’t true. It’s known by various names such as Farmer’s Ear, Surfer’s Ear, Swimmer’s Ear. The correct name is exostosis, where the bone grows to protect from the cold. It takes year of exposure to develop, but it’s very easy to protect against: by simply wearing ear plugs when swimming in cool or cold water. I’ve been swimming or surfing in very cold water (by Texas standards) for decades and I’ve always worn ear plugs, and have no problems, and always list them as essential for cold water swimmers. Hope this helps.


  6. Pingback: Cold Water Acclimatization | LoneSwimmer

  7. Well I don’t know but two days ago after waiting almost two months to go for a swim (long story) yeah my head hurt like a bastard! Just didn’t want to keep it submerged for for very long. it felt like 10 ice cream headaches. i had a neoprene cap and a swimming wet suit. Swam 800 meters and couldn’t feel my feet afterwards.
    Today I put on my 5:4 winter wet suit a silicone and neoprene cap fins a weight belt to counter the buoyancy of the thicker wet suit and hey presto no ice cream headache frozen head. I’m guessing core body temperature effects this feeling to a point? Think I might try a short 100 meters in speedos and back with the neoprene cap and see if I get the same ice cream headache as the first swim produced.


    • Hey Sam,

      No, I don’t know if core temp has anything to do with the ice cream headache. It never has been linked for me. Habituation is lost more easily than acclimatisation and your most temperature sensitive nerves (thermoceptors) are in your face and hands. But you also habituate to cold water entry very quickly. Also, don’t rule out the intangible. You could have had an low level infection which made you more sensitive also, but which you wouldn’t necessarily feel.


      • Interesting thoughts Donal, a low level infection never crossed my mind. At least that would explain why my face and hands were so uncomfortable..
        The plan is to transition from the wet suit to the speedos relatively fast. The reduction in swimming time will be made up by an increase in sensitivity and thus heightened awareness of the ebb flow and flux both internal and external. On that note wet suits do have the capacity to cloud the mechanics of such things potentially resulting in a false sense of security. The dangers of which exist more so at the entry level and intermediate end of cold water swimming.


  8. You’re a surfer?! Amazing. Me, too, although don’t do it much these days (living inland now). But love that shot of Ballydowane Cove. I can see the waves wrapping around that point with the right swell direction. Anyhow, back to swimming…

    Good post (as usual). One thing you don’t mention, and that I experience, is head pain in very cold water. Not sure if it’s a headache or what. Also my skin hurts.

    I also wonder if some people are just anatomically set up to stand cold water more. Take Lynn Cox, for example. She once told me (we knew each other back in Southern California) that she just doesn’t get very cold. Which might explain why she’s probably the greatest cold-water swimmer of all time. (see her book: “Swimming to Antarctica”)

    But there is NOTHING like a hot shower after a cold-water swim. Nothing.

    Q: Why do you always refer to temps in C? You use the Imperial System for Length, no? (feet, miles, etc.), or are you now on Metric? So no Fahrenheit temps, eh? Alas, we here in the U.S. still use F.


    • Hey Harald, I’m afraid only the USA, Burma and Liberia don’t officially use the Metric System! Imperial units are used unofficially here amongst people, mostly only weight and distance, and the older people use Fahrenheit, but every winter I have to relearn the Fahrenheit measurements, as I think in Celcius and metres.

      I should have mentioned the headache, Sam also refers to it in another comment on this post. I do have another post on it that I might bring back also.

      Yes, I recall Lynn Cox mentioning the lab measurements in the book, and how she displayed anticipatory thermogenesis, her core temperature escalated before swimming. It was really interesting, but the fact that we suffer means we cant be as good, but w can understand each other better, I think.

      Finally, I’m afraid I no longer refer to me myself as surfer. It’s over a year since I put a board in the water, though there are still 6 of them in the shed. I’m afraid at this stage I’d have to relearn my skills. And because it’s prevailing onshore wind here on the south coast, one of the early things that grabbed me about ow swimming, was that I was less at the mercy of the wind, and I could get in the sea more often than as a surfer. Ballydowave isn’t as good as it looks though, it’s all rocks just below the high tide line, on the rare occasions it’s surfable, the next cove over is the best break on the local coast, even though it’s a beach break. But that little shark-fin shaped island in the picture does have a hollow centre and tunnel that runs through it.


  9. I tried the cold Cape Water on Sunday after many years. I swam for 20 minutes behind the waves. It was a most thrilling experience and I was hot when I got out. (Only to be very cold 20 minutes later but the warm sun sorted that out.


  10. People ask me if I like swimming in cold water. I don’t. It is shocking, the cold never abates and I regularly lose the feeling in my hands and feet…and on occasion other, more sensitive, parts too. But the after effect – wow. And the mental discipline of going, “I am cold, but I can bear it and I am not going to die. And the sun, wind, rain or whatever is on my back that day reminds me that I am a super sensate being.”


  11. Pingback: Extreme cold adaptation in humans, part 2 | LoneSwimmer

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