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Where Science Meets Lifestyle.

Beyond the Ice: How Cold Water Immersion Can Transform Your Body and Mind

Searching for optimal health and wellness can seem like a bottomless pit. Thankfully TheBiohack is here to provide you with the raw facts. We’ll try to sprinkle in some humour along the way too. Todays topic is one I’m sure you will have come across on your social media feeds. More invigorating than your morning espresso, but more mentally challenging that almost anything else. It’s time to explore cold water immersion (CWI).

From icy dips in natural waters to shiver-inducing cold showers at home, this practice isn’t for the faint-hearted. It’s a call to the wild that promises various health benefits, from sharpened mental clarity to enhanced physical recovery. But exactly how do you get started? And how do you stay on the right side of safety? Please keep reading, and we’ve got you covered.

Leading the charge into the frigid waters is none other than Wim Hof — aka The Iceman. Hof has not only popularised embracing the cold, but turned it into a cornerstone of health improvement. Alongside CWI, Hof employs ancient breathing techniques and some good old mindset training, to fully optimise the experience. His methods claim to boost energy, enhance the immune system, improve mood and aid with weight loss1.

Nature, though, has no mercy, especially when it comes to the cold. The dangers are real and severe. Yet science is playing catch-up. For as many exciting new findings as there are, there are many that leave us with more questions than we started with. So, let’s explore the past, present, and future of CWI so we can safely access its amazing benefits.

Evolution & Our Physiology

Our animal body is hundreds of thousands of years old. Much older than the evolved social environment through which we view and interact with the world. We are designed to cope with the cold, but our modern surroundings protect us against this reality. Sadly this means that most people choose the psychological comfort of our cozy environment rather than exploring the benefits that can be derived from periods of discomfort.

Should you choose to explore this discomfort, it will take sheer determination. But venturing into the cold is more than a test of will — it’s an invitation to witness the wonders of human physiology in action. As the chill in the air bites, our bodies adapt with a symphony of responses designed to shield us.

Our first response is peripheral vasoconstriction, a strategic manoeuvre that narrows the blood vessels in our skin and extremities. This initial response reduces heat loss and ensures that our internal warmth stays where it is needed most — around our vital organs.

Next, our metabolism shifts up a gear. Calories are burned in exchange for an increase in heat. This is our internal thermoregulation response. This is coupled with a significant release of adrenaline (aka epinephrine) and noradrenaline (aka norepinephrine) in the brain and body. These neurochemicals boost our arousal (alertness), and make us feel as though we need to move during the exposure — this is a feeling we have to fight in order to trigger the adaptive responses to CWI.

Finally, shivering. While shivering can be a sign that it’s time to seek a warmer environment, its function is as involuntary as it is vital. These muscle contractions are the body’s way of stoking its internal furnace, generating heat through an effective burst of metabolic activity. Shivering is uncomfortable, but it’s undeniably a brilliant last-resort survival mechanism2.

Benefits of Cold Water Immersion

Turning down the temperature can turn up the health benefits. Firstly, improved circulation. Cold exposure sends blood coursing through the body with renewed vigour. Enhanced blood flow not only strengthens the cardiovascular system but also plays a role in reducing inflammation3.

It also is a rallying call for our immune system. Regular forays into the cold have been linked to increased white blood cell count and an overall more robust immune response. The promise here is persuasive: a bolstered defence system and a potential reduction in infections4.

Cold exposure also helps with body recomposition. Repeated exposure activates brown adipose tissue (BAT), which is a fat-burning powerhouse. BAT produces heat via an active process that directly burns calories to produce heat5. (The alternative type of fat is white adipose tissue, which is essentially blubber. No active heat generation, just insulation as the result of excess calorie storage). If you’re looking to shed excess fat, cold exposure should be a non-negotiable alongside regular exercise and healthy diet.

And for the physically active, it’s a well-known fact amongst athletes that cold exposure can soothe and restore muscles. It’s a natural remedy offering a reprieve from the aches and pains of intense physical activity through its anti-inflammatory effects6.

The benefits of a regular leap into the cold extend beyond the physical. It’s a dive into mental clarity. Studies and personal testimonies alike speak to the mood-lifting and anxiety-alleviating effects of cold water immersion7. This could be attributable to the dramatic rise in dopamine following cold exposure8.

Emerging evidence also points to other remarkable benefits: from alleviation of chronic autoimmune inflammation, to enhancing haematological and endocrine function, reducing fasting glucose levels, and optimising the body’s handling of dietary fatty acids9 10 11. Think about it this way…evolution has equipped us with the necessary tools to thrive in the cold but we’ve been too busy living in comfort to notice our lack of discipline to embrace it.


The icy embrace of cold water exposure can invigorate the body, but it’s not without its hazards. These risks, whilst particularly potent for those with pre-existing health conditions, remind us of the need for caution and expert guidance.

Hypothermia and frostbite are the two most known adverse effects. To mitigate these, you should slowly build up your tolerance, starting at a higher temperature and keeping your sessions short (5 – 10 minutes maximum).

There’s also a documented potential risk of heart arrhythmias12. This underscores the importance of understanding your health before exploring CWI. Keep yourself safe with the oversight of a clinician or expert who knows your circumstances.

Finally, a note to gym goers and those seeking muscle growth: Scientific studies have shown that CWI can inhibit the inflammatory response13. This is good for preventing soreness but bad for muscle growth and repair. To mitigate this, you should keep your muscular training and your CWI at least four hours apart.


Do you still want that beach body? The one you keep dreaming of? Forget the extreme diet. Summer is just around the corner, and the warm air is the perfect accompaniment to your first experiences with CWI. Add it to your exercise regime and a healthy diet, and you’ll soon achieve your goals.

CWI is powerful. Fortify your body. Fortify your mind. Fortify your discipline. Fortify your health. But never forget your limits.

CWI can be a central tenet in your path to optimal health and vitality. Your body is designed for it. From the evolutionary tools at our disposal to the benefits already discovered, we have enough reasons to embrace the cold. But as we move forward, let us do so with a spirit of informed curiosity.

Further Reading

If you’re interested in learning more about cold therapy, here are some further reading suggestions that I think you’ll enjoy:

  1. What Doesn’t Kill Us: a book written by Scott Carney. An author that has made a career out of disproving health guru’s and questionable lifestyle advice. Scott spent time with Wim and was so shocked at the results he wrote this fantastic book on his experience. A must read.
  2. The Wim Hof Method: a book written by the Ice Man, Wim Hof. Another must read for your personal journey in to cold exposure.
  3. Whole-Body Cryotherapy in Athletes: From Therapy to Stimulation. An Updated Review of the Literature: This review article provides a comprehensive overview of the current state of research on whole-body cryotherapy and its potential benefits and risks14.
  4. Cold water immersion therapy: do the benefits outweigh the risks? This article provides a good overview of the risks and benefits, balanced with interviews from experts15.


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[NB. All images created using Midjourney]

Welcome to The Biohack – Where Science Meets Lifestyle.

The Biohack: a unique fusion of medical expertise, neuroscience insights, and athletic excellence, dedicated to guiding you on a journey toward optimal health and well-being. Our mission is simple yet profound: to provide reliable, scientifically-backed health and lifestyle resources that challenge the misinformation often found in today’s digital landscape.