This article is careful, deliberately. Skin is a clinical subject at the point where anything is actually wrong with it, and this publication does not do clinical. What we can usefully cover is the environmental interaction, which is the bit that belongs to swimming, and the everyday care that follows an ordinary cold swim. Where it stops being ordinary, we stop.
Cold removes the signal that limits exposure
The everyday regulator of how long people stay in the sun is discomfort. You get hot, you get bored of being hot, you move. Cold water, wind and repeated immersion remove that regulator completely. A swimmer in cold water on a bright day feels cold, and cold prompts you to stay out in the sun longer rather than less.
This is why cold water swimmers and open water groups sometimes get significant sun exposure on days that did not feel like sunny days at all. The wind chill and the water temperature made it feel like a grey morning, and the ultraviolet index said otherwise. As covered in timing an outdoor session, the index does not track how warm it feels.
Feeling cold is not information about ultraviolet. It is only information about temperature.
Wind does two separate things
It cools. Which compounds the effect above and also matters for the getting warm problem afterwards.
It dries and abrades. Wind on wet skin, particularly with salt or with cold, is physically drying. Anyone who swims outdoors regularly in winter recognises the effect on the face and hands. It is an ordinary environmental effect and it is why the everyday care after an open water swim is a little more than after a pool swim.
Ordinary care after an ordinary swim
This is described as everyday care and nothing more. It is the same advice anybody would give about being outdoors in cold weather.
- Rinse. Fresh water to get salt or lake water off, where facilities allow. Many open water sites have none, in which case a container of water in the car is what people do.
- Dry properly. Including the parts that stay wet: behind the ears, between the toes, under a wetsuit's edges.
- Get warm and get dressed. This is the priority after cold water and it outranks everything else on this list.
- Moisturise if your skin feels dry. Ordinary emollient, ordinary use, nothing special about swimming.
- Look after lips and the parts that get wind and sun together. Lips, nose, ears.
Everything above is everyday care. If skin is painful, broken, blistered, spreading, weeping, not settling, or if you have a rash you cannot explain, that is not a swimming question and we will not answer it. The right route is a pharmacist, who can help with a great deal, or a GP. For sunburn, including when to get help, see the NHS page on sunburn. For persistent skin conditions, the NHS and the British Association of Dermatologists patient information are the sources. We do not diagnose, we do not treat, and we do not offer opinions on anybody's skin.
Wetsuits change where the exposure lands
A wetsuit covers a large proportion of skin, which changes the exposure map rather than removing it. What remains exposed is the face, the neck, the hands, and often the back of the neck where the suit sits lower than people expect. Those are precisely the areas that receive the reflected component discussed in reflection and the water surface.
Wetsuits also produce their own ordinary skin effects at the edges, from rubbing, particularly at the neck. That is a fit and lubrication question that open water communities discuss extensively, and it is ordinary chafing rather than anything we would characterise further. If it breaks the skin, it stops being ordinary and the previous section applies.
Does cold change the skin question?
Indoors the water is warm, there is no wind, and the skin question is about repeated immersion in treated water. See skin after chlorine.
The indoor equivalent of the missing signal problem is different: warm humid halls make long sessions comfortable, so duration is not limited by discomfort there either.
Outdoors, cold and wind remove the discomfort signal that would otherwise limit exposure, so a cold bright day produces long exposures that nobody planned.
Afterwards, the priority is getting warm. Sun protection for the standing about segment and something to put on both matter, and both are usually forgotten because everybody is concentrating on being cold.
Getting warm and dry after a cold open water swim
Owns bringing what they need: a change of clothes, something warm, a towel, water to rinse with if the site has none. Owns getting out before they are too cold to manage the getting out. Owns knowing that cold does not mean the sun has stopped.
Owns it for a group, and owns knowing that a group standing about cold on an exposed shore is both a welfare problem and an exposure problem at the same time. Owns the recall, the head count, and having somewhere for people to get warm. Owns recognising when somebody is not recovering and escalating rather than managing it.
Where there is a venue operator, owns changing facilities, rinsing water, shelter and warm drinks. Most open water locations have none of these, which is a fact to plan around rather than a complaint.
Where a duty attachesCold water guidance from the RNLI. Skin and sunburn guidance from the NHS, the British Association of Dermatologists and Cancer Research UK, sun, UV and cancer. Nothing here is medical advice.
Lips, ears, nose and hands get everything at once
In cold open water, most of the body is either submerged or covered. What is left is a short list, and that short list takes the wind, the sun, the salt and the cold simultaneously: lips, the tip and underside of the nose, the ears, the back of the neck where a wetsuit sits lower than people expect, and the hands.
Those are also the areas that receive the upward reflected component described in reflection and the water surface, because a swimmer's face is angled up at the surface repeatedly while breathing and sighting. So the exposure concentrates on the few square centimetres that are neither covered nor submerged, which is why open water swimmers develop a distinctive pattern of weathering on exactly those areas.
The everyday response is unremarkable: cover what can be covered, look after lips, and remember the ears, which are almost never included in an application and are one of the most frequently affected areas at any swimming venue.
The hour after the swim
The most underestimated part of a cold water session is the period after getting out, and it is underestimated in two directions at once. It is where the cold problem peaks, because a body continues to lose heat after leaving the water and a swimmer standing about wet in wind is still cooling. And it is where the exposure accumulates, because it is the longest continuous outdoor period of the session and nobody is thinking about anything except being cold.
Both problems have the same solution, which is convenient: get dressed properly and quickly, in something that covers you. A swimmer who puts on trousers, a long sleeved top and a hat within a few minutes of getting out has addressed the rewarming and the exposure with one action, and has also stopped standing about in swimwear in the wind, which is the thing everybody does and nobody plans.
Summary
Cold and wind make you feel like the sun is not happening. It is. Plan the exposure for the whole session and bring something to put on for the long cold standing about part, which serves both purposes at once. Afterwards, rinse, dry properly, get warm, and moisturise if you feel dry. If anything is actually wrong with your skin, that belongs to a pharmacist or a GP, and this article stops there deliberately.