Skip to main content

Does Cold Water Exposure Really Have Scientific Backing?

Dr. Mark Harper, Chase Jarvis

Does Cold Water Exposure Really Have Scientific Backing?

Dr. Mark Harper, Chase Jarvis

buy this class


Sale Ends Soon!

starting under


Unlock this classplus 2200+ more >

Class Description

There's a common misconception that artists have a monopoly on creativity...But the very act of making waves - no matter the career - is a creative one. The Chase Jarvis Live Show is an exploration of creativity, self-discovery, entrepreneurship, hard-earned lessons, and so much more. Chase sits down with the world's top creators, entrepreneurs, and thought leaders and unpacks actionable, valuable insights to help you live your dreams in career, hobby, and life.


If you’ve been a reader of this blog or a listener of my podcast, the Chase Jarvis LIVE show, you know I’m obsessed with cold water exposure. That’s what I was excited to have Dr. Mark Harper on the show to discuss new studies and stories around how cold water swimming and cold water exposure benefits the body’s overall function.

Dr. Mark Harper is a consultant anesthetist at Sussex University Hospitals (UK) and Kristiansand (Norway). He is also a leading expert in hypothermia prevention in surgical patients, therapeutic benefits of cold water adaptation, and open-water swimming. And his latest book is coming out in July of 2022: Chill: The Cold Water Swim Cure – A Transformative Guide to Renew Your Body and Mind.

Dr. Mark was interested in finding a way to prevent the harmful effects of the body losing temperature regulation during surgery. He then realized that cold swimming was a lightweight stressor that one could build on daily to make the body stronger and more resilient to regulate temperature appropriately.

In this new book, he combines science with case studies of his patients to prove the physiological and mental health benefits of cold water that help relieve chronic pain, arthritis, anxiety, depression, PTSD, migraines, fibromyalgia, autoimmune diseases, and more.

The Magical Feeling of Swimming in Cold Water

One of my first and certainly most memorable experiences swimming in cold water was a New Year’s Day polar plunge in the San Juan Islands in Washington. The water was frigid, but something about that experience grabbed my attention.

I felt an electric feeling better than caffeine – and it was all-natural. This single experience triggered what eventually became my daily cold water practice.

After some time, I noticed that I had stopped getting sick. For several years I never caught a cold. I was going through difficult times at work, working between 60-80 hours a week. But the pressure and stressors from all that seemed to moderate or dissipate.

As much as the cold water can be discouraging, knowing the bliss that awaits on the other side gets me into that water. Before ever reviewing the science or hearing from experts like Mark, I was bought into the power effects of cold water.

The Physiological Effect of Cold Water

According to Dr. Mark, cold water creates stress, and that stress ignites a massive nervous system reaction.

Water has a high specific heat capacity, which is what gives it the ability to draw cold out of the body. It sets off adrenaline and noradrenaline, similar to how a drug like cocaine does.

The body becomes naturally “high,” and a great amount of stress is relieved.

If you suffer from disorders such as autoimmune diseases, depression, mental health challenges, trauma or post-traumatic stress disorder, or chronic pain, Dr. Mark’s guidance will help you tap into cold water’s healing power.

Basic Biological Mechanisms

Cold water, like exercise, alleviates post-traumatic stress and promotes post-traumatic growth. Not only that, but cold water adaptation reduces inflammation. (Note: Cold water swimming is simply swimming in water and cold water adaptation is when a swimmer goes through chronic exposure to the cold water environment and develops a degree of adaptation.)

Through research, Dr. Mark realized that cold water is a stress factor with similar effects to a surgical operation. He concluded that if cold water swimming could minimize stress, then the stress from surgical procedures could also be reduced by cold water swimming, lowering the number of complications.

The stress response from cold water is because of the water’s absolute temperature and the body’s cooling rate. Taking a regular cold shower or standing under the coldest water environment you can create in your own house for about 3 minutes can give you similar benefits.

After seeking clarification about how cold water triggered the responses, Dr. Mark gave a simple explanation that I could easily understand. The sympathetic response is activated since my limbs are in the water. When I immerse my face, the diving reflex is stimulated, which is a parasympathetic response.

The vagus nerve takes control of my body; I feel rested, digestion is boosted, relaxing hormones make me happy, and inflammation is reduced.

If this sounds like a huge commitment, fear not. Although the benefits are greater with more cold adaptation, you can see results almost immediately.

The Achievements of Chill (Cold Water Therapy)

The strongest study that Dr. Mark and his team have conducted so far is on depression and anxiety. Cold water therapy has proved successful in alleviating clinically diagnosed depression and anxiety. Dr Mark and his team ran clinical patients under various courses with a recovery rate of 70 to 80%.

Of all the patients under selective serotonin re-uptake inhibitors (SSRIs) taken in by Dr. Mark, 50% showed a response, and 70-80% recovered at the end. The best part is that recovered patients have continued to thrive in good health after 3-month follow-ups.

Dr. Mark’s book also profiles five people who’ve benefited from cold water. From fibromyalgia to long-term antidepressant use or even migraines, cold water therapy was the cure.

Cold water therapy is not only for those with various conditions. It’s a powerful biohacking tool accessible almost anywhere, whether in an ocean, city park, lake, sea, bathtub, or a sink in your home.