Medical evidence on the benefits of cold water swimming is limited, but more and more research is being conducted into the topic. If you are tempted by the increasingly popular pursuit, what can you expect to gain from it physically and mentally?
Extending your outdoor swimming season maintains a connection with the water and with nature. A healthy dose of fresh air and the chance to swim in open water is appealing, even uplifting, and you can stay in touch with some of the skills that will help you next season.
Swimming in cold water has lots of reported benefits from aiding recovery and reducing inflammation to boosting your immune system and reducing stress and anxiety. Some swimmers also say that they don’t feel the cold and therefore don’t need to turn their heating on – helpful during a fuel crisis!
However, outdoor swimming in winter comes with a whole set of safety considerations. It’s not open water swimming, it’s cold water swimming. It’s a different discipline and you need to give up on ideas of swimming a certain distance or for a certain amount of time. You also need to invest in the right cold water swimming gear and make sure you’re fully prepared for every swim.
Cold Water Swimming Benefits
The benefits of cold water swimming appear to be wide ranging, although not fully researched or documented by the medical profession. Starting early in the winter season and accepting the safety aspects and time it will take to adapt and acclimatise, you can extend your outdoor swimming to cover the whole winter – there is no such thing as ‘too cold’ if you’re properly prepared.
This really depends. If you’ve not prepared yourself for it, then it could be really bad and land you in the local hospital. Those that train specifically for it may experience a boost in endurance, reduction in inflammation and a mental high from completing each swim.
Improved recovery through cold water immersion
It’s generally accepted that sitting in an ice bath provides a sporting benefit – or else lots of professional athletes simply like to torture themselves. Applying this logic to cold water swimming suggests that engaging in winter swimming and dipping is also beneficial.
It’s hypothesised that cold water immersion (CWI) post exercise promotes recovery (noting that stretching, massage, sleep, compression and nutrition also form part of an overall recovery strategy). This happens through physiological changes to hydrostatic pressure, redistribution of blood flow and reductions in core and tissue temperatures.
An article in the International Journal of Sports Physiology and Performance said, “there is evidence that CWI reduces thermal strain, swelling, inflammation, limb blood flow, muscle spasm and pain.”
To get any benefit, you need to immerse yourself for somewhere between 5-15 minutes in 10-20 degree water, depending on your individual characteristics. If you’re doing it regularly, 1-5 min per immersion will bring about benefits.
The good news for triathletes, is that in terms of promotion of recovery, athletes with lower body fat percentages can benefit the most from CWI.
A study referenced in the International Journal of Sports Physiology and Performance also evidenced improved performance by cyclists taking part in distances above 1km time trial that engaged in regular CWI.
Increased immunity after cold water swimming
There’s not much evidence of immunity being boosted by swimming in cold water, but scientifically, it’s possible. Getting into cold water causes a stress response which may trigger an increase in white blood cells. Anecdotally, winter swimmers often boast that they have fewer coughs and colds during the winter than their non swimming peers.
Weight loss through cold water swimming
Calorie counting isn’t a reason to get into cold water, but fat loss could be a side benefit. Swimming in cold water takes a lot of energy, both during your swim and afterwards. A study by the University of Copenhagen found that men who swam in cold water (1-9 degrees) used, on average, about 500 extra calories per 24 hours compared with people who did not.
Mental health benefits of cold water swimming
Cold water swimming alone is dangerous, hence you need ‘your tribe’ around you. There’s the opportunity to attend coached and group sessions with others, and it’s generally a sociable activity where you get to connect with other like-minded people.
Case reports in the British Medical Journal report that cold water swimming ‘may’ be an effective treatment for depression and a BBC documentary charted a young woman who used cold water swimming to successfully come off antidepressants.
Scientists and doctors agree that getting into cold water brings about a stress response that gradually reduces over time as you repeat the exercise more. This reduction in stress translates into other areas of life, you become more capable of dealing with stress – ‘cross-adaptation’ is a process where one form of stress adapts the body for another.
Cold water swimmers report an immediate improvement in mood following each swim, and it’s helped people with depression, anxiety and PTSD.
Potential Negative Effects Of Cold Water Swimming
Asking a doctor, who swims all year round off the Gower coast in Wales, UK, if he had any medical evidence about the benefits of cold water swimming, he replied that it wasn’t something he had come across within medicine ‘other than the A&E scenario of falling into cold water’.
The negative effects are well documented, ranging from cold water shock, hypothermia and even death. No one should attempt to take up cold water or ice swimming without having properly prepared, researched, and even undertaken a specific training course.
How to avoid cold water shock
According to the Royal Lifesaving Society (RLSS), cold water shock can happen in almost any body of water, even in summer – particularly if someone falls in by accident. There is the initial shock of being immersed, which causes you to gasp for breath and hyperventilate. That can be followed by blood pressure shooting up as the body tries to keep the blood warm by moving it towards the middle of the body.
We’ve probably all seen videos of people cutting holes in thick frozen ice to reveal the icy water below and then getting in for a swim. Apparently, there’s no such thing as ‘too cold’ if you’ve prepared in advance and have the right safety provision.
For those unable to get out of the water, muscles will cool, preventing further movement – ‘swim failure’. Without assistance, drowning is likely at this point.
This is why cold water swimming coaches such as Fenwick Ridley refers to such concepts as ‘feeling thermally comfortable’ when swimmers first get into the water and centring yourself on breathing.
How to avoid hypothermia
The NHS defines hypothermia as “a dangerous drop in body temperature below 35C (normal body temperature is around 37C). It’s a medical emergency that needs to be treated in hospital.”
It is possible to become hypothermic whilst swimming in any water that is cooler than body temperature (so, that includes indoor swimming pools), but obviously it’s more likely and can happen more quickly in very cold water.
Avoiding hypothermia is a matter of experience – gradual introduction to cold water swimming. Getting out of wet gear and into dry, warm clothing as quickly as possible after swimming is also essential.
The short answer to this is yes. There’s a risk of cold water shock within the first 60 seconds of getting in, and you can start to develop hypothermia after about ten minutes. If you have an underlying illness, hypothermia can start even sooner. There can be serious complications from hypothermia, including death.
If you are still keen on exploring winter swimming then check out our list of UK cold water pools, lakes and other venues. Don’t forgot to take the necessary safety steps and pick your equipment carefully and you will soon be enjoying the benefits of cold water swimming.