4th December 2022:
With so many swimmers dipping their toes into winter, we get a lot of questions when the swimpond water temperature plummets – specifically, a lot of these 6 questions. Here, we answer them all in one place.
1. WHAT DOES IT FEEL LIKE?
Winter swimming is a challenge, a physical assault on the body. With its immediate effect on blood pressure, it is literally not for the fainthearted. Cold water will punch the air out of your lungs, it will bite your hands and feet off. Cold drives the sense out of you. Cold water can leave you shaking coffee all over yourself, unable to do up your own bra strap. After the cold wears off you have an incredible buzz, a sense of exhilaration and achievement.
2. IF IT’S X DEGREES, HOW LONG CAN I STAY IN FOR?
Once upon a time, somebody, somewhere, said something like ‘you can stay in one minute per degree – above 10-degrees.’ This has gone through the urban myth wrangle and come out as a broken (rule of) thumb: ‘double the degrees C to get time in the water’ (no mention of the 10 degree boundary) and ‘you can swim twice as many lengths as the water is degrees’ (no! Don’t do that). All of these answers are wrong, perhaps dangerously so.
There is no universal answer to how long you can stay in for, it depends on your body. Start out with small dips, see how you are after you get out, extend your time in the water gradually and make the journey into cold your own personal experiment. You will find there is not even any reliable answer to ‘how long can I stay in?’: how much cold an individual body can take will vary from day to day, depending on sleep, health, hangovers, stress, recent acclimatisation, what’s been eaten and time of day.
The question about ‘how long can I swim?’ is really a question where the ‘edge’ is for you – the edge between a swim being safe or risky, being pointless or worthwhile, being enjoyable or bad. Do you want to cold swim, then go on with your day – or is the physiological switch you’re flicking only available to you if you get so cold it stays with you for hours afterwards?
3. WHAT’S THE BEST WAY TO ENTER THE WATER – SLOWLY OR JUST JUMP IN?
The best way to enter water is slowly, in a controlled way. One of the first things you will learn to control as a winter swimmer is the ‘gasp’ reflex, where it feels as if the cold water has punched the air out of your lungs, and you cannot breathe. If this happens to you: exhale with a strong ‘fwaw’. This may feel counterintuitive but if you puff the air out the next breath will come back in. Then concentrate on steading your breathing rate and taking a few steady head up breaststrokes. Stay in the shallows until you can control your breath so that, if need be, you can stand up or walk back out.
4. WHAT’S THE BEST WAY TO WARM UP AFTERWARDS?
Thermal regulation is so important to the vital organs that the thermo-regulatory system trumps others (such as hydration levels) to maintain a thin band of survivable body temperatures.
The first thing that your body does when entering cold water is to start to shut down blood to the skin to conserve heat. The skin and fatty layer then become an insulating buffer zone to protect the core – your very own ‘bioprene’. The thicker the layer of fat, the better the insulation it provides. ‘Cold diuresis’ occurs as this happens – you generate a lot of pee. Over time blood may also leach out of the muscles, this is how ‘cold incapacitation’ occurs in a swimmer: their muscles become incapacitated by cold, making strong swimmers weak.
When you get out from a swim, this process reverses: blood returns to the skin, and cools down in the process. Therefore you will be at your coldest 10 minutes after you get out.
The best way to see yourself through ‘afterdrop’, is to change immediately. Dry yourself off (pat, don’t rub), add lots of warm layers, and have a warm drink. Put yourself in a warm place. See The Subtle Art of Warming Up for more tips. And don’t drive until you feel well.
5. DO I NEED BOOTIES, GLOVES & HAT?
Winter swimmers vary widely in what they wear – from thermal wetsuits and neoprene accessories to bobble hats and swimming costumes. Neoprene booties and gloves are effective in reducing pain to the hands and feet of very cold water.
Head gear (whether bobble hat or neoprene bonnet and swim hat) can help with warmth.
Submerged in very cold water in a swimsuit, with wind and rain whipping through your hair, the old wives that 50% of heat is lost through your head is closer to being true than ever. The body can achieve a 99% reduction in blood flow to the skin between the extremes of vasodilation (up to 6 litres of blood to skin per minute) and vasoconstriction (blood flow down to 0.02 litres per minute).
The only place this does not occur is the head – blood flow to the scalp remains similar across all conditions. This does not mean your mental function is unimpaired – one of the dangers of winter swimming is hypothermia and bad decision-making.
Cold water in the ears can affect balance – some use ear plugs to reduce dizziness. (You can also do head up breaststroke).
6. WHY DO IT?
People love winter swimming for all the philosophical, physical, social, and physiological reasons there out there. There has been a noticeable upswing in people doing it for pleasure, rather than just as a practise in endurance, in recent years.
‘I do it because I can, I do it when I think I’m going to explode. I do it when I’m feeling a bit ill. I started doing it regularly after my dad died, and it sort of became the only thing that helped. To be honest it’s become a bit of an addiction. This year, I didn’t want to do it, but I knew it would improve my mood, so I carried on. Some days I think I should be able to control my temperament more easily, without throwing myself into freezing water but, I live by a lake and ‘whatever works!’
I do it as an exercise in stoicism, a practise in ‘not minding’. I do it as a mini-adventure in a pretty domestic life (I have two under 10s). A day when I fit in a freeze or a run before school drop off is a good one. (As Robert Macfarlane put it, ‘discomfort has become its own luxury.’).
So, whether you do it to just to keep swimming, to keep up with swim friends, or for the physiological and psychological changes you feel it induces (an increase in happiness perhaps, a reduction in anxiety): enjoy. And swim safe.
Yes, can winter swim right off the back of your patio in your very own swimpond.
