Photo by hryckowian

Everybody has seen or been that guy at one point, who is standing out in literally freezing weather without a jacket of any sort, proclaiming that he isn’t cold. You chuckle as you point out that he must be cold since he’s doing such a poor job of hiding his shivering.

Of course, he just replies that hanging out in the cold makes you tougher, implying that you are some kind of warm weather weakling.

Machismo aside, standing outside in freezing temperatures without a jacket is a pretty decent display of toughness. But, does this kind of behavior actually make you tougher? Or, does it set you up for catching a cold like every mother has been saying since the dawn of time?

Fight or flight?

Norepinephrine is a hormone and neurotransmitter in a group of chemicals called catecholamines, sympathomimetic “fight-or-flight” hormones released by the adrenal glands in response to stress. It works in concert with epinephrine (commonly called adrenaline) to jump start the body’s response to potentially life-threatening situations. Their release into the body causes various things to happen, like increasing heart rate and mobilizing stored glycogen. Typically, conventional thinking will refer to these hormones’ immune suppressing capability.

The idea is, that perhaps the immune  system isn’t as critical as glycogen mobilization while running away from a bear. I don’t think that simplistic explanation really makes sense. What happens if that bear is diseased and manages to get a good swipe at your back with his claws? There could be a host of pathogens scrambling to get inside of that wound.

This is where norepinephrine really starts to shine. You see, the actual effect catecholamines have on tissues during acute stress events is remarkably variable depending on the tissue and the situation. For instance, norepinephrine facilitates tissue repair [1] at wound sites and mobilization of leukocytes [2] to the location.

Rather than suppressing immune response, acute stresses actually seem to enhance it.

According to a study by the Army Research Institute of Environmental Medicine, says Dr. Belilovsky. “Researchers examined the immunological responses to cold exposure and found that acute cold exposure, such as going outside without a jacket, actually appears to activate the immune system.” [3] This occurs in part by increasing the levels of circulating norepinephrine, which works as a natural decongestant.

The key word here is “acute”. These stressors, like a wound or cold air exposure are sharp and temporary. The body senses the danger, activates hormones, and delivers a response. The immune system becomes markedly compromised when the hormonal response becomes dysregulated due to chronic stress exposure. Your body is just not equipped to deal with chronic stresses like nerve-wracking 12 hour work days, or prolonged severe cold exposure.

Beyond activity at the cellular level, there is a process by which one can face cold exposure and actually become more capable of attenuating the stress response. This is called hormesis, the physiological phenomenon where mild acute stresses can stimulate an organism or tissue to become stronger. [4]

It has become increasingly popular to utilize this mechanism, and is probably most often triggered on purpose by taking cold showers. [5] After getting over the initial shock response of the cold water, the body’s ability to regulate heat through thermogenesis will kick in and a few minutes later the water will feel more comfortable. Do this on a regular basis and you will probably experience a noticeable increase in cold water tolerance.

When does hormesis become hypothermia?

Of course, there is the evil twin version of this mechanism called hypothermia. One only needs to mention the sinking of the Titanic to invoke a fear a falling into frigid waters. What most people don’t realize is that the human body actually is hot enough to prevent heat loss in freezing water for up to 30 minutes. [6] What killed all of those unlucky passengers was that they were stranded in the freezing Atlantic ocean for far longer, and lost core body heat from swimming. Tragically, the need to tread water causes the body to lose heat faster, and the numbing of limbs eventually makes it impossible to stay above the water.

In a basic way, this is another illustration of the differences between acute and long term stressors, and how the body can cope up to a point. A cold shower is an acute stress, typically only a few minutes of cold water exposure. It’s just enough to get the body excited and activate it’s catecholamine response. Engaging in this type of controlled and intermittent training will make you tougher.

Slogging your way through a marathon during a blizzard, or immersing yourself in icy water for hours on end will do the opposite. If you don’t die outright from heat loss, your body’s organs and peripheral systems will be compromised just from the shear need to keep core functionality like your brain operational.

So, will cold exposure make you stronger or weaker?


If you plan on doing some hiking or trail running this winter, be sure to dress appropriately. I wouldn’t want your mom to get worried.

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32 Responses to Does Cold Exposure Make You Stronger Or Weaker?

  1. Michael says:

    This is good stuff. I’ve never really liked cold showers before but maybe I’ll give it a try now. It’s pretty cold already though this time of year.

    • David Csonka says:

      I admit, in the winter time the cold shower is twice as harsh. Once when getting in, and then again when wet and confronted with cold air in the house. Just make sure you have a thick robe near at hand!

  2. Manolis says:

    I did some experimenting some years ago with cold showers. Living in a relatively hot enviroment it is only natural to have cold showers during summer. I wanted to see how long I could go on having these cold showers in the winter. Well, it last for a couple of years. I remember people would either wouldn’t believe me or would think I am crazy. What I know is that I realy enjoyed it.

    Also, as a student at central Europe I used to go to the (dry) sauna every now and then. My favourite part was the immersion in an ice-cold bath, which was usually situated outside in the snow, immediatelly after 10-15 mins of 95 degrees Celcious dry sauna. After the initial shock, I remember how clear my head was and how strong and calm I used to feel.

    • David Csonka says:

      Interesting Manolis – can you explain for me what is different about a “dry” sauna? Is that just heat without added steam? What you describe sounds to me reminiscent of the ancient Roman fondness for alternating hot and cold baths.

      • Manolis says:

        “Dry” I call the kind of sauna that just heats up the air and there is practically no steam. “Wet” or “Turkish Sauna” (as opposed to “Sweedish”) on the other hand would be the kind of sauna Romans used to have, where I got a feeling of being in a hot cloud, despite the temperature being much less than the dry one.
        Personally I prefer the former. It’s much more social (you actually see the person next to you), hotter and obviously more dry, which helps with sweating.

        • David Csonka says:

          I see what you mean, and it makes sense. In South Florida the humidity is typically pretty high in the summer, making it feel far hotter than it really is. It’s like being in the jungle I suppose. The dry heat of the west, like in Nevada, didn’t make me feel as miserable as long as I remembered to drink plenty of water.

  3. Andre says:

    My naturopathic doctor actually recommended contrast showers, where you run the water cold three times during a regular warm shower. I have been doing this most days for about a year now, and I really notice that I don’t feel very cold on the contrast shower days. It also seems to help with circulation in my hands, which have a tendency to get cold. I recommend them to everyone!

  4. Aaron says:

    Great timing on this post!

    I’m doing a Tough Mudder run in late January – 9 miles with many obstacles that involve cold water and mud. I’ve been thinking of ways to improve my tolerance to cold and wet into my training routine in preparation. Obviously I need to switch to cold showers for a while. I was also thinking of doing some of my outdoor exercise when it’s cold and rainy.

    I’m very open to any other ideas that fall on the “good” side of the cold exposure so I get stronger and I don’t get sick.

    The Tough Mudder itself seems like it may be too long and be on the “bad” side – but it looks like too much fun and challenge to pass up.

  5. David Csonka says:

    Aaron, you might want to read this article as well: – it talks about some situations where endurance athletes pushed past the cold discomfort and finished (but with injury). Are you doing the mudder event in Austin, Texas?

    I’ve read a few articles which pointed out how endurance athletes will commonly experience immuno-compromise for a period of 24-48 hours after a hard competition. I think the key here is acclimation and maximizing recovery time. Don’t let race day be a complete shock to your body, give yourself at least a week to recuperate afterward.

    • Aaron says:

      Thanks for the link, I’ll check that out.

      Yep, I’m doing the one in Austin.

      I am running on Saturday, resting on Sunday. I plan to take the following Monday off from work and probably won’t do much in the way of exercise and such during the entire following week.

      • David Csonka says:

        Good call. Best of luck with the race, those things look insane. The braveheart charge looks fun! :D

        • Aaron says:

          So it’s been a while but I thought I’d come back and leave a follow-up comment. This is entirely subjective because I don’t know a way to measure “cold tolerance” , but I believe cold conditioning definitely helped me through the Tough Mudder.

          For two months I took almost exclusively cold showers. I went running occasionally in the cold and/or rain. I avoided wearing a coat during the winter so every ‘home-car-work-car-store-car-gas station-car’ transition exposed me directly to winter air.

          I live in south Texas and I think I’m better adapted to the cold now than when I lived in the north and wore layers of warm clothes and big coats.

          I did great in the Tough Mudder. I’ve since taken several long runs through cold weather in a t-shirt or less just because I can. It’s kinda fun to regulate my own temperature by increasing or decreasing my running rate.

          Now, If I get cold – I don’t look for a coat, I break into a sprint.

          • David Csonka says:

            That’s awesome Aaron. Did the Mudder meet your expectations? Since my move to Denver (form Florida) I’ve been working at increasing my cold tolerance. I look pretty nuts going for shirtless walks around the lake in 40 degree weather, but I think it’s working.

          • Aaron says:

            The Mudder was awesome. I highly recommend this event to just about anyone who asks me. The course, the obstacles, the people – everything was great. Very challenging and very fun.

  6. Ευάγγελος says:

    Well,cold explosure really does make you stronger!
    I’m a winter swimmer!I love sea and i just can’t stay away from her at winter time.So i don’t!Sea water gets really cold in winter time and someone has to be really carefull to get in there!But after a few minutes in the deep cold winter sea,you feell great!As soon as you get out (time in,depends by many reasons) you feel your body working 100%!Soo strong emotion!!!I defetenly recomend that!
    After a few times in cold sea,cold showers really seams like a joke!
    And as it concerns getting a flu…not in a million!

    • Manolis says:

      Way to go David! Half the comments come from Greece on this post.
      ????????? I am glad I am not the only Greek reading this amazing blog.
      I wish I would have the courage to be able to swim during winter. The feeling you describe really rings a bell and it’s great. I am in the middle of exams at the moment but I will certainly look into it as soon as I finish.

      • Ευάγγελος says:

        Hey hey Manolis!We meet again!Remember me from the “barefoot running page” on Facebook?
        To tell you the truth,i’m the one who does get jealous!Beaches here in Attica has nothing to do with those in Crete!Lucky you mister!
        Good luck on your exams!And then have fun in the great winter sea!

        p.s. For those who do believe in natures power and energy flowing everywhere..they say that sea in winter time is the best way nature can offers you all that!Well i believe they are right!

    • David Csonka says:

      I think I have been spoiled by the warm waters of the Gulf of Mexico. When I was a child, I lived along the Atlantic Ocean, and I remember it being much colder than what I am used to now.

  7. Andrew says:

    When I lived in Panama, I didn’t have hot water in either of my apartments. It was 93 every day, 71 every night, and interspersed with 1-2 cold showers daily. I moved back to Portland on a December 30th and was wearing scarves and shivering ’til May.

    Having also grown up in Alaska, I do think there’s something to heat/cold acclimatization, but I’m not sure about the mechanism(s). Elevation adaptation seems to be real as well which speaks more to our adaptability in general.

    Isn’t there something to the spicy foods in hot climates thing? I seem to remember something about consistently eating hot foods tends to downregulate perspiration, etc.

  8. Can’t speak to cold showers being healthful, but I can say that hot showers were doing something weird to my skin. This was pre-paleo, but for years I had dry skin and dry scalp. Once I went paleo and quit hot showers, both disappeared.

  9. JP says:

    Good post,

    I can definitely link this with my own experience.

    I live in Canada and it’s pretty cold during the winter.
    Anyway, one winter, whenever I would leave home and go somewhere that I knew was warm (aka work, a friend house, etc), I would only wear shorts and a hoodie. Whenever i knew I would spend a lot more time outside, I would wear pants and a coat.

    anyway, this is all to say that I was not sick even once during the winter. I was actually in pretty good shape. I really was not freezing whenever I would be outside in shorts (never more than 20-25minutes).

  10. DS says:

    Hi there
    find the exact opposite, the Paleo diet actually makes me warmer, maybe its cause of the fats in the diet. I often find myself wearing less than carb/sugar eaters.