Cold Water Awareness

Paddleboarding in winter is great – it’s often incredibly still and serene, with much less traffic on the water. It may even be relatively warm and sunny, tempting you into going out there without too much protective clothing. Which can be very dangerous indeed…

The big problem is if you fall in to cold water, without adequate clothing. Your body has some instant and automatic physiological reactions to a sudden immersion in cold water, which unfortunately can potentially be lethal. The commonly held assumption that hypothermia is the main danger from cold water is totally false – the cold shock response and loss of muscle function will kill you long before you succumb to hypothermia!

Cold shock response

This is the first thing that happens. It lasts about a minute while your brain and body adjust to the shock of the cold water, and includes all sorts of instant involuntary body reactions (ie you cannot stop them happening!), such as sudden increase in heart and blood pressure that may result in cardiac arrest, even for people in good health. Even more deadly is the gasp reflex, which can cause you to inhale as you go under the water, and drown without coming back to the surface. If you suddenly suck a bunch of lake/ocean into your lungs, you’re in a very bad way indeed. Especially as other aspects of the cold shock response are vertigo, so you don’t know which way is up or down, and vastly reduced breath hold capacity anyway. This is why, if you choose to go winter paddling without a wetsuit or drysuit that will protect you from this cold shock response, then wearing a PFD (not an inflatable one!) will hopefully keep your head on the right side of the surface, dramatically increasing your odds of survival.

Loss of muscle function

Assuming you do make it back to the surface after falling in, your plan will of course be to get back onto your board as quickly as possible. You lose heat 25x quicker in the water than out of it. You really do not want to be hanging around in cold water. Your body cuts off the blood flow to the extremities, and quite quickly, they simply stop working. You’ll lose meaningful movement in your hands and feet first, then your arms and legs. It can take as little as 5 minutes for you to lose the ability to simply grab something to pull yourself out of the water, and 15 until you can’t even swim at all.

So – most importantly – you really really really do not want to be losing your board when you’re paddleboarding in cold water conditions. Make sure your leash is in excellent condition. Don’t even think of going paddling without one. And if the worst case scenario happens and you do get separated from your board, then just be aware that you really only have a few minutes to make emergency calls or whatever, before your fingers will stop working.

How cold does it need to be?

You can experience cold water shock in water under 15°C. The colder it is below that, the quicker and more severe it will be.

How can I avoid it?

For any sort of SUP activity where you really are likely to get wet regularly, such as SUP surfing, then a wetsuit is a must. For paddling in super cold conditions on lakes and slow rivers, then a dry suit is an excellent idea. If you’re paddling on sheltered waters and are not expecting to fall in, then it’s still really smart to wear a permanent-buoyancy PFD, just in case you do slip off or get knocked in – so you are protected against that initial cold water shock. And if you’re not going to be wearing a wetsuit or drysuit, be sure to be wearing the right clothing – see below.

How to dress?

Dress for the water temps, not the air temps. You want to keep dry and warm; dry means not getting all sweaty as well. This can also be dangerous.

The 3 important layers include

  1. Wicking base layer – draw the moisture away from your skin.
  2. Thermal layer – ideally something that will keep you warm even if it gets wet like wool, fleece, etc
  3. Waterproof shell. You may not be 100% water tight but this layer should keep you from getting soaked if you go in the drink.

Above all AVOID COTTON! It soaks up water, gets very heavy and it actually works to reduce your body temp when it gets wet. As the saying goes, “Cotton kills.”


If you or one of your paddling crew does get wet and cold for an extended period of time, then hypothermia may become a factor. This occurs when the body core temperature starts to drop into the danger zone. It usually takes at least 30 minutes to kick in, because the body does a pretty good job at conserving core temperature for as long as possible. So how do you recognise it? Watch for the “Umbles” – stumbles, mumbles, fumbles, and grumbles, which show changes in motor coordination and levels of consciousness. Basically, the person start to act like an angry drunk! This can be easy to miss if you’re on your own, but may well be noticeable in someone else.

Hypothermia is very bad news and needs to be dealt with as quickly as possible. Call 111, you have an emergency on your hands!

The important thing is to restore warmth slowly:

  • Get the person indoors, if possible
  • Remove wet clothing and dry the person off, if needed.
  • Warm the person’s trunk first, not hands and feet. Warming extremities first can cause shock.
  • Warm the person by wrapping them in blankets or putting dry clothing on the person.
  • Do not immerse the person in warm water. Rapid warming can cause heart arrhythmia.
  • If using hot water bottles or chemical hot packs, wrap them in cloth; don’t apply them directly to the skin

If the person stops breathing, start CPR immediately. Hypothermia causes respiratory rates to plunge, and a pulse might be difficult to detect.

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