What are the benefits of cold water swimming? Pros and cons of winter swimming

Cold water swimming has grown in popularity in recent years, with more wild swimmers looking to continue swimming outdoors all year round.

Swimming in cold water has plenty of reported benefits. From the physical – such as aiding recovery and bolstering your immune system. To the mental, such as reduced stress and anxiety, and a feeling of overall wellbeing after spending time in nature.

As more and more people choose to ditch the pool and instead don their wetsuits (or just their swim suits if they’re a brave soul!) to head for a chilly dip in open water. You might be wondering if cold water swimming is for you. To help you decide, we take a look at the benefits of cold water swimming – and the potential drawbacks to be aware of.

Benefits of cold water swimming

While more research still needs to be conducted to fully understand the potential benefits of cold water swimming, plenty of anecdotal evidence suggests the benefits can be wide ranging.

Before you dive headfirst into the world of cold water swimming though, it’s important to understand that you need to take your time to adapt and acclimatise. Start with short amounts of time in the water, staying in standing depth. You might even want to think about practicing at your local lido – many offer cold water swimming sessions during the winter months – to build up your tolerance to the cold before you go into open water. With the right preparation, precautions and cold water swimming gear – there are plenty of upsides to braving the cold.

Cold water immersion can enhance recovery after training

For amateur triathletes, being able to recover faster between training sessions is always going to be a major benefit.

It’s been suggested that cold water immersion (CWI) may promote faster recovery after exercise. An article in the International Journal of Sports Physiology and Performances states that “there is evidence that CWI reduces thermal strain, swelling, inflammation, limb blood flow, muscle spasm and pain.”

The cooling effect can help to reduce inflammation in the muscle tissue, alleviating any acute pain after exercise. Cold water can also help to improve blood circulation. Initially, the immersion in cold causes blood vessels to constrict – reducing blood flow to the muscles. But once you get out of the water, the vessels quickly dilate as you warm back up again. The subsequent flow of blood to the cold limbs helps with the delivery of oxygen and repair agents to the muscles, and the removal of waste substances. This in turn helps to reduce muscle soreness after training sessions.

Being able to recover faster between workouts and adapt to training stimulus more effectively will help you to train with greater consistency, which in turn can benefit your overall performance.

Boosts your immune system

Alongside helping you to recover faster between training sessions, braving chilly swims may also help you to avoid disruptive winter lurgies such as coughs and colds. Another benefit of cold water swimming is said to be a boost to your immune system. A 2011 study* investigated the blood composition of 15 healthy subjects after they participated in a 150m swim in 6 degrees C water. The results showed a significant increase in their white blood cell count. These white blood cells act as the body’s defence warriors, helping you to fight off bacteria and illness.

Alongside stimulating the production of white blood cells, cold water swimming can also help to reduce stress and promote better sleep – in turn putting you in a better position to fight off any nasty winter bugs.

*Effect of winter swimming on haematological parameters, 2011, Lombardi, Ricci, Banfi.

Mental health benefits of cold water swimming

Physiological benefits aside, plenty of cold water swimmers also report a positive impact on their mental health and wellbeing. Being immersed in cold water stimulates the body to produce endorphins, adrenaline and dopamine – ‘feel good’ chemicals which help us to feel invigorated, and even euphoric. The rush of getting into cold water can be a serious mood booster, particularly paired with the ‘in the moment’ mindful nature of focusing on your breathing and staying calm in the cold.

Cold water swimming can also help the body and the mind to become more resilient to stress. It might seem counterproductive, if you’re looking to reduce chronic stress. But the intentional stimulation of the parasympathetic nervous system helps the body to become better at coping with stressors. This can translate into other areas of your life, helping you to reduce your overall stress and anxiety levels.

There’s also a strong sense of community amid cold water swimmers – with many meeting up in groups on a regular basis to swim together. This social interaction, particularly while connecting with nature, can help to reduce isolation and loneliness.

What are the risks and potential negative effects of cold water swimming?

While the benefits may seem wide ranging. It’s important to be aware of the risks involved with swimming in cold water, and the potential negative impacts to your training. So you can make an informed decision about whether it’s right for you.

Cold water immersion may hamper muscle growth

Plunging into an ice bath or going for a chilly dip after training can help to reduce inflammation and soreness – helping you to feel ready to train or race again sooner. But there is evidence that this immediate anti-inflammatory effect after training can actually hamper the adaptations required to achieve muscle hypertrophy (i.e. muscles getting bigger).

If you need to be able to train multiple times a week with little time to recover between sessions, cold water immersion might help you to do so with greater consistency. But if increasing the size of your muscles is your primary goal, you might want to look at other recovery strategies first.

Avoid cold water before training sessions

Timing is another important factor when it comes to incorporating cold water swimming into your routine. While a brisk early morning dip might sound like a great way to kickstart your day, if you need to go for a run straight afterwards you could be putting yourself at risk of injury. Because old water will restrict blood flow to your muscles, and they’ll become tight and stiff, vigorous exercise soon after being in cold water could leave you vulnerable to muscle strains and tears. Give yourself time to warm back up properly, and perform some gentle mobilising activities before you go all out.

Cold water swimming can be dangerous

Swimming in open water at any time of year carries with it inherent risks. But when you bring cold temperatures into the equation, these risks can be amplified. Plummeting water temperatures can increase the risk of experiencing cold water shock – the body’s involuntary gasp reflex is stimulated, which in turns leads to hyperventilation and sensations of panic. Cold water can also bring about ‘cold incapacitation’ where the body diverts blood from the limbs to the core to protect essential organs from the cold. This results in feeling extremely fatigued, with muscle weakness and a loss of dexterity – which can be dangerous if you start to struggle to swim back to shore, or can’t exit the water. Hypothermia and ‘after drop’ (feeling colder after you get out of the water than you did when you were in it) can also be more likely when swimming in colder water.

Finally, the environmental hazards of open water swimming may carry increased risks in the winter months. Stormy winter weather can bring with it strong tides and choppy conditions in the sea. And high levels of rain fall can increase harmful pollution in rivers.

It’s important to swim within your comfort and experience levels, and to ensure you swim in safe locations. Learn more about the risks of swimming in cold water, and how to manage them.

Ready to give cold water swimming a go? Check out our list of UK cold water pools, lakes and other venues. And make sure you’ve got all the gear you need to enjoy the water safely with our cold water swimming gear guide.

Quick recap: Cold water swimming FAQs