Cold. At the very thought of it, most of us have negative associations, and bodily reactions like goosebumps appear on our body. No, it’s not for me-we think. However, what if intentionally exposing ourselves to cold could bring about some health benefits?
Cold for centuries
In the last few years, there has been a significant increase in interest (of my own, too) concerning human exposure to low temperature, especially cold water, and its effects on our physical and mental health as well as on our general well-being. Hardly anyone who has tried cold showers, immersion in tubs with ice water or staying in open water bodies, considers it a pleasant sensation during the experience itself, but nevertheless often repeats it. Why?
For thousands of years, starting with the report from the Edwin Smith papyrus in 3500 BC1, through the information of Hippocrates, Roman physicians, and the surgeon of Napoleon Bonaparte, to modern enthusiasts (Wim Hof) and scientists, humans have been aware of the benefits of cold water immersion for their physiology.
In addition to my interest in the topic of cold water immersion and practicing this activity for over two years, I recently came across Dr Andrew Huberman’s podcast. In the podcast, he describes the mechanism of deliberate (meaning intentional) cold water exposure and its effect on our:
- physical and mental resilience
- anti-inflammatory processes
- mood, ability to focus and energy level.
Dr Andrew Huberman also recommends a specific protocol to get the best results from deliberate cold water exposure whilst following safety rules.
As someone who works with people experiencing sleep problems and their impact on daily functioning, I find the latter topic particularly important and worth sharing with you, my readers. Therefore, from the study conducted by P. Šramek and colleagues2, we learn that deliberate immersion in cold water increases the level of adrenaline and norepinephrine. They are two related hormones responsible for stimulating the body, for example, through heart rate acceleration. At the same time, the study found that exposure to cold water released about 250% more dopamine compared to the levels before the exposure. Dopamine is a hormone and neurotransmitter responsible for not only increasing energy, but also promoting a sense of pleasure, success and motivation. It was realized that the elevated dopamine levels persisted for several hours after leaving the cold water. That’s probably why we repeat deliberate cold water immersion after a few days, despite the initially unpleasant experience.
Interestingly, the study subjects did not show an increase of cortisol. Cortisol is a stress hormone released in difficult situations. Its long-term rise can have a negative impact on physical and mental health, including problems with sleep, concentration or memory.
Also, in the podcast Dr Andrew Huberman cites the example of a person who overcame his drug addiction by replacing it with deliberate cold water immersions. In this case, the level of dopamine, the reward hormone, was increased in a different, healthier way than that in the form of psychoactive substances. Therefore, the deliberate exposure to cold water had a therapeutic effect in this case.
Questions that often arise in connection with the use of cold showers or baths are how often and what temperature of water is optimal to achieve the results described above. Dr Andrew Huberman’s protocol proposes immersion of the whole body up to the neck. Thus, baths rather than showers (there are still relatively few scientific studies on cold showers) would be advised, for about 11 minutes a week. This time is recommended to be divided into 2-4 sessions lasting from 1 to 5 minutes each. Since each person tolerates cold differently, there is no clear answer to the question: how cold should the water be? It may be helpful to say that we should strive to immerse ourselves in the water with the thought, ‘So cold! I would like to get out, but I can safely stay in this cold’. All in all, the temperature of the water should be uncomfortable, but still safe to stay in for a few minutes. The good news is that after some time of regular use of cold baths, it becomes easier to endure the lower temperature of the water and notice its health effects. If you’re ready to enhance your experience, try putting your hands in the water as well!
Cold water immersion and sleep
Please remember that after cold exposure the core body temperature increases. Consequently, we experience acceleration of blood circulation and general stimulation of the body. As a result, practicing cold water exposure will be a good strategy in the early hours of the day for those who would like to give themselves a natural ‘energy boost’. However, entering cold water can disturb our sleep if we apply it in the evening, shortly before going to bed.
In conclusion, if we want or need to improve our mood, increase energy levels and sharpen our concentration, deliberate cold water immersion, combined with safety maintenance and observation of our own reactions, will be a great solution for many.
- Wang, H., Olivero, W., Wang, D., & Lanzino, G. (2006). Cold as a therapeutic agent. Acta Neurochirurgica, 148, 565–570. https://doi.org/10.1007/s00701-006-0747-z
- Šrámek, P., Šimečková, M., Janský, L., Šavlíková, J., & Vybíral, S. (2000). Human physiological responses to immersion into water of different temperatures. European Journal of Applied Physiology, 81, 436–442. https://doi.org/10.1007/s004210050065