Why indeed? Swimming in cold water is potentially dangerous, and up until now I have spent all the winter months almost surgically attached to my hot water bottle, so I'm really not sure, but I know I am waiting, with almost excitement (could be fear, they are said to be closely intertwined), for the water to cool down, and it seems I'm not alone, cold water swimming is fast becoming more and more popular, with many swimmers not only enjoying the cold water, but also claiming to have felt both physical and mental health benefits from it. There is, as of yet, only a small amount of scientific evidence to back this up, but there is more than plenty when it comes to the risks associated with swimming in cold water.
One of the risks is hypothermia, which I shared with you in a recent blog, hypothermia-what-i-needed-to-know.html. Another, and one that people are far more likely to die from (sorry to be blunt), is cold water shock, which unlike hypothermia, happens as soon as you get in the water. Mike Tipton Professor of Human and Applied Physiology at the University of Portsmouth and cold water survival expert says:
"If you're lucky enough to survive long enough to die of hypothermia, you've done very well; most die in the first minute of immersion."I promised my anxious friend that I would read more about cold water and the risks involved and I thought I'd share the information with you, but before I go on please note I'm not a doctor, specialist, scientist, or indeed Guru (unlike my friend), I'm just a swimmer that wants to understand about the dangers, learn how my body will react so I can be better prepared and be able to respond properly, enabling me to enjoy my winter swimming as safely as I can, or worse case scenario, to increasing my chances of surviving. The information below is me just sharing. It does comes from experts, scientists, medical people, accomplished swimmers and organisations, all of which I'm not! These are their thoughts, opinions, recommendations and suggestions. Once again, I must say that some of it may be conflicting, and parts of it that you may not agree with .... Basically, in a nutshell what I'm trying to say is don't shoot the messenger!
Firstly, what is cold water shock?
"It is the body's short term involuntary response to being suddenly immersed in cold water." RNLI (2017)
- Involuntary gasp- this overrides the ability to hold your breath. If this happens and your head is under the water you may drown immediately. One breath is all it can take.
- You start hyperventilating - (this can be as much as 4-5 times your breathing at rest). The rapid breathing can lead to hypocapnia (this is a deficiency of carbon dioxide in your blood), which can cause: dizziness, visual disturbances, anxiety, numb hands and feet, pins and needles, cramp, onset of asthma, chest pains and slower reaction times.
- Your heart rate and blood pressure increases significantly, and your heart rhythm may change as the blood vessels in your skin constrict in response to the cold, by shunting the blood away from your limbs to the core, to protect your vital organs- The increased load on your heart can lead to cardiac arrest or stroke. This is most likely you have an underlying heart condition, however it can happen to even the healthiest of people.
- Your ability to move decreases as the body cuts off the blood flow the the non essential muscles of your body.
- Increased levels of the stress hormone adrenaline in your body - this also increases your heart rate and your blood pressure.
- Dry drowning - cold water hitting your throat can cause it to spasm to stop any water getting into your lungs. Unfortunately, it will also stop any air getting in.
- Your instinct may be to swim hard, however this can lead to drowning as you'll probably be gasping.
- A feeling of panic.
I've include here a video link with Ant Middleton, the ex special forces military veteran and ambassador for RNLI, experiencing what cold shock feels like at the University of Portsmouth. It also demonstrated how cold water affects your motor skills, even after only a short period of time. It's an interesting watch. watch
Cold water shock only lasts for a short space of time. For some it will take less time than others - Everyone is different, but it usually passes in under three minutes. The important thing is to try and remain calm, and know that this feeling will pass.
- Don't jump or dive in (that involuntary gasp underwater means you'll inhale water).
- Try and stay calm and relaxed.
- Wait for the feeling to pass before you set off swimming (or if you do, swim with your head out of the water).
- Float on your back.
- Habituate yourself gradually.
- Keep warm up to the moment you get in- swim coats, hats, gloves, socks, hot drink etc.
- Do some stretches- it should help you to get into your rhythm quicker.
Finally, it's a year since I first began writing my little blog, which stared as a way of writing about my recovery, the training and the swim I did last year (Windermere one way). I have been amazed and overwhelmed at the amazing response, and lovely messages of support I have had. After I had completed the swim I was asked if I would consider putting last year’s journey into a book. Going from a blog to an e-book is something quite different, and a lot scarier, however I decided after a lot of consideration to take the plunge (no pun intended) and do it, and finally has now been published this week on Amazon. How amazing (but mostly scary) is that? I hope that for those of you that read it feel inspired to not only take on difficult challenges, but also to never underestimate how far you can push yourself to achieve what you set out to do.
|Open Water Woman Swims Windermere is available on Amazon|
Bibliography and points of reference (in no particular order):
https://www.myevolve.org/ (for Coach Morg).
Tipton MJ (1989) The initial responses to cold-water immersion in man. Editorial Review, Clinical Science, 77: 581-588.