How cold is “Cold Water”?

There is no magic number of what constitutes ‘cold’.  Yours, mine and the next person’s ‘cold-ometer’ is going to be different and that’s okay. Be independent and responsible in your own ability to assess how much you can tolerate and become familiar with how your body responds to the lower temperatures.

For your personal safety, it is vital to be aware of your limitations in cold water.  Also don’t give in to peer pressure to do more than is comfortable or safe for you at any given time.  Likewise, don’t put pressure on other swimmers to do more than is safe for them.

Here we are focusing on winter swimming.  Let’s assume that the water temperature is below 10c (less than 5c is classed as ice swimming) cold enough to take your breath away when you get in.

It’s important to realise that many factors are going to affect, and change, your day to day tolerance of cold, for example:

  • How you feel
  • How you slept
  • What you ate
  • Stress levels
  • Other training sessions you’ve done
  • Air temp., wind, rain, hail, snow

You may have spent a comfortable 10mins in the water yesterday but that doesn’t guarantee it’ll be safe for you to stay in for 10mins today or tomorrow. Always be observant of how you feel ‘right now’ before you enter the water.

If you are completely new to cold water swimming, your body will acclimatise quite quickly; the pain of the first time will lessen (slightly) with each dip or swim.  Apparently, your body will also hold that acclimatisation even if you only then manage to get in occasionally!

Am I OK to swim?

Sometimes it can be too easy to make excuses not to train or swim, but we also need to be brutally honest with ourselves about when it is actually not OK to do so. If you are, or have recently been unwell, then use good judgement as to when it’s OK to get back into the water and also how much you can do; take it easy with a short dip the first day back after illness.

You must also consider more serious health conditions. If you have any history of cardiac illness, talk to your doctor first before swimming throughout the winter. If you’re given the OK to go into cold water, then enter the water slowly and steadily.  NEVER jump into the cold water. Wearing a wetsuit is a good option for anyone with any cardiac history as it can help reduce the initial shock reaction of the body.

Sea Water vs. Fresh Water?

It is often said the sea water feels warmer than fresh water.  In lakes, even when the temperature readings are the same, this seems to be true. The lack of movement of lake water and lower water density than the sea, keeps the fresh water feeling colder.

In very cold weather when still water freezes, the water closest to the surface of a lake is the coldest, where this is not the case in the sea.

Rivers are at their most unsafe to swim in during the winter as currents run fast and strong. Heavy rain makes them unpredictable and along with the cold, they should never be considered safe for winter swimming.

Have I been in too long?

  • Are you shivering in the water?
  • Are your arms getting heavy or sluggish?
  • Do you feel warm (or even hot)?
  • Have you lost the ability (or even the desire) to actually turn your arms and swim?
  • Are you numb?
  • Have you loud ringing in your ears?



Even during your regular swim or dip, there are TWO simple ways to check if it’s safe for you to continue:

  1. Can you talk? Have a little chat out loud to yourself and see can you actually form words.
  2. Can you coordinate? Use your thumb to touch each finger in turn on the same hand.

Loss of hand and speech coordination can indicate the start of a hypothermic state, it’s time to get out of the water.

NEVER be afraid to say “I don’t feel OK”

In it for the Buzz!

Winter swimming gives an amazing endorphin rush, and can leave you feeling so full of life it’s really quite hard to beat.

As the water gets colder, the thrill gets bigger but the time in the water gets shorter.

Whilst a quick ‘teabag’ dip or a few minutes swimming can give you a fully energised buzz that will see you smash your day, a slightly longer cold swim can leave you tired. That tiredness can linger all day.  This is not good when you’ve a busy day of work, so plan your dips to fit your schedule.

Acclimatise yourself by swimming or dipping regularly and form good habits to stay safe – hypothermia is not pleasant for you or your swim friends.

There are many members of Atlantic Masters swim club who are very experienced winter swimmers.  We also have a few fabulously hardy ice swimmers (Dee, Fergal, David C) so never be afraid to ask for help or information. Pop a message onto the WhatsApp group, or to the Facebook and Instagram pages. Also, you can email the secretary if you would like to be linked up with, or directed to groups of swimmers.


Equipment – What do I need for winter swimming?

The amount of ‘kit’ you bring with you is completely personal. There is no need to have ‘all the gear’ before embracing the cold water, but self-care and comfort should be a primary thought in your preparations.  You will acquire kit that works best for you as you swim more.

  • It’s handy to have more than one set to avoid putting on damp gear when swimming on consecutive days
  • Swim hats. Wear two latex hats or one latex with a neoprene hat underneath. I have read lately that for dipping, the ‘bubble’ style hats are warm, cheap and easy to put on as part of a layering system. The outermost hat should be brightly coloured to help you be visible in the water.
  • Ear plugs. Silicone mouldies, plastic fitted ones or even blue tack (ask David C). Surf Ears are very popular, they are expensive but good in that you can actually hear with them in.
  • Good goggles. If you’re putting your face in these are vital to stop your eyeballs from getting ice-cream freeze when the water is really cold
  • Neoprene gloves and socks/booties can help retain heat in hands and feet; they also protect them from cuts and grazes.
  • This is optional but can be useful for longer swims.
  • Flipflops/slides/crocs to walk to and from the water. They make walking with numb feet much easier.
  • Tow float. An important safety device for open water swimming and makes you visible to other water users.  Use a permanent marker to put your name and an emergency contact number on it, plus it’s a good idea is to have a whistle attached
  • Changing Mat. Something to stand on to change after your swim can prevent further heat loss. You can get all manner of fancy mats but a rubber car mat and scrap of an old towel work too.
  • Towel or towel robe
  • Woolly hat
  • Gloves
  • Warm socks
  • Roomy footwear that’s easy to put on; avoid laces if you can.
  • Hot water bottle. I wrap my clothes around one and then use it to warm my kidneys on the drive home! DO NOT empty the contents of a very hot water bottle onto your cold self or apply the hot water bottle directly to the skin.
  • A large bottle of warm tap water. Wrap your clothes around it, and then use it as a warm shower/hand & foot warmer after swimming.
  • Layers of loose, easy-to-put-on WARM clothes. I read a quip recently regarding undergarments yes/no…? That’s a decision only you can make but I have utmost respect for all who can put on a bra or a pair of skin-tight jocks after. As for tights, DONT DO IT….it can only end badly
  • Hot drink. This is best in a travel cup with lid as it prevents a lot of shaky spillage; be careful that it’s not scalding hot.
  • Cake! Biscuits, buns, chocolate, sugary snacks help restore energy.
  • Dry robe or equivalent. They can be an expensive purchase but there are SO many options available now.   They’re not essential but oh so cosy when you’re getting dressed exposed to the elements.
  • Small first aid kit in the car. This is very handy for when you find the rocks in the murky water

Positive Habits for Safe Winter Swimming.

Along with a good dose of common sense, and being able to not overthink the “Will I, Won’t I” element of winter swimming, it is necessary to be prepared EVERY time you go for a swim or a dip. This will increase not only your safety, but also your enjoyment.

  • Don’t swim alone. If you’re unable to meet a group or a swim buddy, dip rather than swim; let someone know that you’re going in and especially that you got out again!
  • Check the weather and tides before you go. Even if you are accustomed to a swim spot in the summer, it can be very different in the winter when the wind chill can sap your strength in minutes.
  • Know your swim location. Learn about the tides and how they work; swells, rocks, other water users such as fishing and leisure craft.
  • Know your kit. Be prepared, check it before you leave home to make sure you have it all with you.
  • If there is no shelter for changing, park your car with the front facing into the wind so the boot, with your gear, is more sheltered for getting dressed when you get out of the water.
  • Have a warmed towel, hat, clothes laid out ready in the order for getting dressed. Leave lacers untied.
  • Get straight in the water after togging; don’t stand around getting cold.
  • Wear two swim hats as the temperature drops. “Ice-cream head” is a common sensation and usually passes quickly but it is true that we lose a lot of heat from our heads
  • Wear plugs. They prevent ear pain, dizziness and possible damage from regular exposure to cold water known as Surfer’s Ear.
  • Wearing a wetsuit helps many people to continue swimming throughout the winter, especially when swimming long distances. It may not be necessary for quick dipping as it can get counterproductive, it takes longer to get changed afterwards!
  • Enter and exit the water in a safe and easy place. This location may change according to the tide; stumbling over rocks is very difficult with numb feet.
  • Enter the water slowly. It helps to splash water onto your face, neck and arms as you go in. Do NOT dive in! Your body’s natural shock reflex response will cause you to gasp, and then to hyperventilate.  One big gasp under water is more than enough water to fill your lungs and cause drowning, even in the strongest of swimmers.
  • Control your breathing before you swim when the shock is strong! Making lots of noise can help (Mike???) and take a minute or two of gentle swimming for it to settle. The shock response peaks at 30 seconds and adapts at around 2 minutes
  • Swim parallel and close to the shore, and do short laps
  • Get dry and dressed quickly after getting out of the water. You may feel glowing and warm, especially after a short dip, when first getting out but this will pass quickly as your body temperature will continue to drop. This is known a Post Swim Drop, so you have a few minutes before the shaking starts.
  • Put on a towel or robe, dry your head and put on a beanie and remove any wet swimming gear. Continue to dry and dress yourself as your core body temperature will drop further after getting out of the water and drops to its lowest after 30-60mins.  Try not to get distracted, dress warmly in plenty of loose layers.
  • Have your warm drink to hand, sip it as you get dressed.
  • Look out for others around you, both in and out of the water. Look for signs that they may be hypothermic eg. struggling to get dressed, slurred speech, seem distressed.
  • Embrace the post-swim chat and the hanging around drinking tea in a windswept car park. It’s a vital part of the winter swimming experience but  its also beneficial to have a few minutes to ‘settle’ and recover before driving.
  • Going for a brisk walk when dressed will dramatically speed up the warming process.
  • Change your socks 30-60mins after getting dressed, they will be damp from condensation!! (Fergal gave this gem of advice and keeps a spare pair of socks on the radiator at work)

To each and every person swimming, dipping, splashing, dunking, tea-bagging, I applaud you all.  BE SAFE AND ENJOY!

And to those tougher than tough amongst us, REMEMBER, experience does not remove the dangers of cold water, just as acclimatisation does not give immunity to cold or hypothermia.