This month we are very excited to review the eagerly anticipated ‘Winter Swimming’ by Dr Susanna Søberg from Maclehose Press. We’ve long been fans of her knowledgeable and scientific approach to winter swimming so we jumped at the chance to dive into her new book. First impressions are everything and the quality of this book shone through from the outset. A beautiful shot of a solitary swimmer in a glassy flat expanse of water with the quote “The Nordic Way Towards a Healthier and Happier Life.” We are huge proponents of the transformative effect that swimming in cold water has so eagerly leapt straight in.

But first some background on Dr Susanna Søberg. She is a Danish Metabolic Scientist, Bestselling Author, Speaker and OA Breathwork Instructor. She earned her doctorate focusing on the metabolic system as well as on creating and carrying out clinical studies. Her latest research was conducted as research for this book and looked at the effects of winter swimming on fat reduction at the Tryg Foundation's Center for Physical Activity, Denmark. Alongside this highly scientific streak is a passionate winter swimmer, someone who’s as at home in a lab as a lake. In short, she is someone who puts her money where her mouth is and practices what she preaches. It is this combination of empiricism and rationalism that makes for such an interesting author of a book on winter swimming.

“Life is too Exciting to Stay Neutral”

Dr Susanna Søberg

First up the guide is beautifully designed, equally at home on a coffee table as a display book or on a bookshelf. It’s also packed full of exquisite photos. Initially, we open with an evocative shot of two ladies plunging into icy breakers with a cargo ship in the background. Flick through and there are closes ups of bristling red toes gripping iced swim ladders, jubilant swimmers with fists raised as mist rises on a sunny winter day with -20 degree air temperature. Whether images like these or shots of a sandal-wearing swimmer strolling through the snow on his way to a dip in Hampstead Ponds, there is a strong sense of the powerful grip of the lure of the cold. These images of icy vistas and freezing temperatures don’t appear hostile in any way. Instead, they inspire a sense of belonging, as if the human swimmers are meant to be diving into ice-cold water and the bare bodies are at home in the icy environs.

The images throughout are brilliant and are generously spread within rather than sandwiched in the middle as some other books do. This helps pull you in and I was stopping regularly throughout to write down the name of a swim location from the caption of a photograph. Excellent for any budding winter swimmer swim-list.

But this isn’t a guide in the traditional sense, it is much more than that.

What really sets this book apart is the science. Dr Susanna balances detailed and anecdotal introductions on why people swim in winter and how they go about it with truly insightful and groundbreaking passages on what has previously only been anecdotal in the winter swimming community. Long have swimmers waxed lyrical about the mental and physical benefits of winter swimming, about how it makes them feel fitter, stronger and healthier. But here, Dr Susanna takes us through the why.

She guides the reader stroke by stroke into the cold water and forensically details things like the "cold-shock response", describing a massive and measurable endorphin rush as our body interacts and adjusts to the cold temperature of icy water as one swims through the winter season. She further elaborates that not only does human physiology instinctively respond positively, but in addition, our mental health, metabolism and immune system do as well.

The chapter on Brown Fat is a particular treat. Brown fat has always been something of a myth in the swimming world, almost acting like an unseen extra organ of the hardy ice swimmer. But Dr Susanna expertly reveals the truth behind this kind of fat and explains that the brown colour of the adipose tissue can be explained by an increased number of mitochondria in the cells, many more than in white-fat cells. In short brown fat is working incredibly hard for the swimmer. It is keeping them healthy when they’re eating, sleeping, running and most importantly when they’re cold. In fact, she reveals that it is at work constantly to benefit the winter swimmer.

Furthermore, she clarifies that studies have shown that the sudden and intense cooling of the skin post-swim accounts for a dramatic increase in noradrenaline, which activates brown fat. This is an under-researched field and we are only truly beginning to explore the scientific benefits of cold exposure of which dr Susanna is at the forefront.

Another illuminating chapter is the chapter on Winter Swimming and Mental Health. This was one of the chapters I was most looking forward to as personally myself and both my brothers have felt significant improvements in our mental health through continued cold water swimming. She starts by acknowledging the increase in ‘happiness’ hormones such as noradrenalin and beta-endorphins released as part of the cold shock response and goes on to question whether winter swimming could relieve mental disorders as well. In one section she and her research team are at a winter swimming club in Copenhagen, speaking with some swimmers who are interested in her research. One of the group comes over and says to her “It doesn’t matter how, for me it’s just healthy, I can feel it! It’s working here and here!” pointing to his head and heart.

But Dr Susanna wants to dive deeper, and in this highlight of a chapter interviews winter swimmers who are using the icy water to combat substance abuse and addiction as well as depression and seasonal affective disorder. The anecdotal evidence is sufficiently compelling to have us diving for our swim suit and praying for a snowy day. But if you weren’t convinced yet she follows it up with a chapter called ‘In the Sauna’ which had us yearning for the combination of ice-cold water and hot sauna!

“Happiness is the Highest Form of Health”

Dalai Lama

This is truly an excellent read, Dr Susanna is an excellent science communicator and has a knack for a compelling narrative. She enthuses the scientific sections with lyrical swimmers anecdotes and this is all the more rewarding for the reader. she closes the book by saying “Every winter swimmer has their own reasons for taking up the sport, and every story is unique. For me as a scientist, listening to these stories has made the science meaningful and important.”

This is really the crux of why the book is so successful in conveying its message of why winter swimming gives such a boost to body and soul. Dr Susanna Søberg is one of us, she lives and breathes winter swimming, she loves it and has a true passion for it and this passion, combined with her thorough scientific research, makes this essential reading for any winter swimmer.

You can check out the book and get a copy of it - now