Water droplet creates ripples in surface of water

Cold Water Shock

The term ‘Cold Water Shock’ refers to a range of natural reactions that our bodies take to protect us when we enter cold water (although these reactions can sometimes work against us). 

What are the signs of Cold Water Shock?

There are three stages of Cold Water Shock:

  1. The first sign of Cold Water Shock is a gasp for breath, followed by rapid breathing (also known as hyperventilation). 
  2. As you lose control of your breathing, your blood pressure will shoot up as your body tries to keep your blood warm by moving it towards the middle of your body.

    Once your breathing is back under control, this is your window to get out of the water before the further effects of cold water shock kick in. 

  3. As your muscles cool, your strength, endurance and muscle control will reduce and you'll likely find you can no longer swim. This is called ‘swim failure’ and, if you haven’t got out of the water or managed to get hold of a buoyancy aid, by this time, you will drown. 

Is Cold Water Shock really responsible for lots of drownings? 

It is difficult to identify if Cold Water Shock was the cause of a drowning or not, but this is what we know:

  1. All waters around the UK are cold enough to induce the cold shock effects, even in summer months
  2. More than 60% of drownings involve people who have ended up in the water by accident
  3. A sudden rise in blood pressure can be fatal for people with a pre-existing heart condition. Each year a number of people who are suspected of drowning, turn out to have had a heart attack
  4. Studies show that people’s ability to swim in cold water is much less than their ability in a warm swimming pool
  5. Survivors of drowning have described how the effects of cold water shock made it difficult for them to survive

What should you do if you fall into the water? 

First, keep your mouth away from the water until you have your breathing back under control, you can do this by rolling onto your back and floating or paddling to stay at the surface. 

Then, don’t waste any time and swim towards an exit before your muscles start to cool. If you aren't able to exit the water, swim towards something that will help you to stay afloat whilst you are calling for help. 

Finally, once you are out of the water re-warm yourself as soon as you can to avoid hypothermia.

What to do if you experience Cold Water Shock

Click to watch this great video from the RNLI, which features important information about what to do if you find yourself in cold water.

Remote video URL

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