Dealing with Cold Water Shock

Anything below 15°C is defined as cold water and can seriously affect your breathing and movement, so the risk is significant most of the year.

Lake Windermere can be very cold - and takes a long time into the Summer Season before temperatures are above 15°C

Cold water shock causes the blood vessels in the skin to close, which increases the resistance of blood flow. Heart rate is also increased. As a result the heart has to work harder and your blood pressure goes up. Cold water shock can therefore cause heart attacks, even in the relatively young and healthy.

The sudden cooling of the skin by cold water also causes an involuntary gasp for breath. Breathing rates can change uncontrollably, sometimes increasing as much as tenfold. All these responses contribute to a feeling of panic, increasing the chance of inhaling water directly into the lungs.

This can all happen very quickly: it only takes half a pint of sea water to enter the lungs for a fully grown man to start drowning. You could die if you don't get medical care immediately.

If you enter the water unexpectedly:

• Take a minute. The initial effects of cold water pass in less than a minute so don’t try to swim straight away.
• Relax and Float to Live.
• Keep calm then call for help or swim for safety if you’re able.