When Wendell Stevenson decided to retreat to her Breton home by the sea after the end of a 10-year long relationship, she discovered one of the best ways to heal was to immerse her body in the cold water of Locquirec Bay in Northern Brittany.

During the pandemic, worldwide, cold-water swimming has become an increasingly popular way to ‘wake up’ the body, to such an extent that wetsuit manufacturers in the US have been struggling to keep up the demand.

Throughout the ebb and flow of changing lockdown rules over the year of the pandemic, one thing has been consistent in Brighton – people swimming in the sea.

Some people wander down to the water with hunched shoulders alone, others with a partner (when the rules have permitted it). On the many Brighton and Hove beaches it is not a rare sight, even on the coldest days, to see people emerging from the water, red skinned, shaking their arms and wrapping themselves up in a towel.

This isn’t anything new. People have been taking the plunge and swimming in cold waters for thousands of years. However, over the last year and in the midst of a pandemic, it has become an activity for the masses, not just that quirky old man with a wiry beard who always wears shorts no matter the weather.

In a year of monotony, many people are searching for ways to feel alive, but what are the real benefits? Is there evidence to suggest it could be a catch all for complex disorders such as major depression, and even physiological maladies such as inflammation?

Of the many supposed benefits of cold-water swimming, or as some call it, cold water immersion, for every physical benefit there seems to be one for mental health/wellbeing.

Speaking on the positive affects cold-water swimming had on her wellbeing in her Guardian article, Wendell Stevenson remarked “I swam every day for three weeks…I felt absorbed by its energy. It was exhilarating.” She continued, “I was crazily high on endorphins. I didn’t want to stop.”

It has long been understood that exercise can improve mental wellbeing, a boost of endorphins can make you feel less lethargic and more positive. So, what makes cold water swimming different from, say, running?

The shock to the system that comes with cold-water swimming/immersion can activate your fight or flight response. Unlike going on a run when the weather is cold, where you’ll likely be wrapped up, immersing ourselves in cold water requires a willingness to experience something entirely out of the ordinary and every day, to challenge ourselves and our bodies.

Mike Tipton, a researcher at the University of Portsmouth, has been studying what these extreme experiences can do to the human body and mind. Talking to Wendell Stevenson he said, “The body is responding with all the stress hormones…you’ll see changes in all of the fight-or-flight biochemical and hormonal responses. It’s raising your heart rate, your ventilation. That’s the thing that makes people say: ‘I feel alive, I feel alert, it wakes me up for the rest of the day.’”

So, how do these physical benefits carry through and affect the mind?

A cold-water therapy group located in Devon has received over 500 member applications since it started last year. It’s co-founder Guy Edwards has stated it is not a swimming group, emphasising on the therapeutic benefits of cold-water immersion rather than just purely physical ones.

Speaking to ITV he stated, “come and get in, get in up to your waist, sit down, enjoy it, have that immersion and then we’ll get out again”. This approach that is so not pointed towards physical exertion could be the answer to getting people with depression out of the house, to experience something new, where losing weight or being active isn’t necessarily the goal.

This therapy group has been so successful it has now opened other nearby branches.

The leader of the Plymouth group, Amelia Elvins, who struggled with anxiety and post-natal depression said, “When you have depression it is such an achievement to get in the water and say you've done something today other than sitting around your house feeling anxious.”

But can these mental health benefits be pushed further? Or is this just one more activity that simply proves to us that something as simple as spending time outside, in nature and with other humans, can be the thing to kick start recovery and healing.

Mike Tipton has something to suggest otherwise. Tipton was involved in a 2018 case study of a 24-year-old woman, who had had major depression since the age of 17. The study had promising, some might say, astounding results.

The study found cold-water swimming “led to an immediate improvement in mood following each swim and a sustained and gradual reduction in symptoms of depression, and consequently a reduction in, and then cessation of, medication. On follow-up a year later, she remains medication-free.”

Not only was this a marked success but the study also suggested something really interesting for the treatment of mood disorders with exposure to new, extreme experiences in the body.

The study stated, “Physiological mechanisms are linked to cross-adaptation, whereby exposure and adaptation to one stressor impacts on the response to another stressor.” In other words, the stress induced by a disorder such as major depression can be combated with the experience of a new, physiological stressor such as the sensation of immersing oneself in cold water.

The study also found that regular cold-water swimming results in a “postswim ‘high’, triggered by the release of beta-endorphins”, which explains the incredible feeling Stevenson experienced.

Something to be particularly mindful of at this time of year when the sea is very cold is that there are physical dangers involved in cold-water swimming. It’s important to note that gasping whilst in cold water can result in cold water entering your lungs which can be dangerous. Another thing, known as “diving reflex ”, can occur when your cold shock response tells your body to breathe too slowly, which slows down the heartrate too much.

These dangers can be avoided with the right precautions. Such as, swimming in pairs or groups to ensure you’re safe from passing out/drowning or starting your new cold-swimming hobby with short, three-to-five-minute water immersion exercises so that your body adapts to the cold shock.

Whether people are finding happiness from cold-water swimming as a result of the supportive community they’ve formed, such as those in Dorset, or finding motivation and energy in the rush of endorphins released at the moment skin touches the icy water like Wendell Stevenson, the fact that solid evidence to support these benefits currently remains as “hypotheses supported by anecdotes” - as Tipton’s study states – doesn’t really seem to matter.

Sure, the fact that dunking your head in cold sea water (or really anywhere) can stimulate “the vagus nerve, resulting in an anti-inflammatory response” is great. But to people lost in depression, or loneliness because of lockdowns, the anecdotes and shared positive experiences of cold-water swimming/immersion are where they really find nourishment.

As Wendell Stevenson put it “I was alone, cut off from friends and family by coronavirus and Brexit, living off savings, emotionally hungover from the break-up – and yet, quite often, I felt strangely marvellous.”

So, instead of looking on in complete and utter bafflement as people disappear under the surface of the water on a clear, chilly spring day, maybe it’s time we all gave it a go? In a year of having so much taken from us, maybe it’s time to take something marvellous for ourselves.