Cold water immersion (CWI) has gained popularity for its physical recovery benefits, particularly among athletes. However, beyond its impact on physical health, it is also emerging as a potential method to improve mental health. By exposing the body to cold water, several physiological responses occur, that can positively affect mood, anxiety levels, and overall mental well-being.

What is Cold Water Immersion?

Cold water immersion involves submerging the body in water temperatures typically between 10°C and 15°C for short durations. It can be practiced in various ways, such as taking cold showers, using ice baths, or swimming in cold natural bodies of water. Cold water immersion is popular among the Body Dynamics Illawarra team, because of it’s emphasis on health, wellbeing and happiness.

Physiological Responses

Several key physiological processes occur when the body is exposed to cold water:

1. Vasoconstriction: The body conserves heat by narrowing blood vessels in the skin and periphery, which increases circulation to vital organs.
2. Endorphin Release: Cold water immersion activates the sympathetic nervous system, leading to the release of endorphins, commonly known as our “feel-good” hormones, which can elevate mood.
3. Parasympathetic Activation: After leaving the cold water, the parasympathetic nervous system, responsible for rest and relaxation, takes over, helping to reduce stress.
4. Cold Shock Proteins: The cold stimulates the production of cold shock proteins, which are linked to neuroplasticity, improving the brain’s ability to adapt to stress.

These physiological responses form the foundation for the mental health benefits of cold-water immersion, which include:

1. Reduction in Anxiety and Stress

Cold water immersion can lead to long-term reductions in anxiety levels by encouraging the body to adapt to controlled stress. The shock of cold water induces an immediate stress response, but over time, regular exposure helps the body manage stress more effectively by enhancing the body’s ability to regulate stress hormones like cortisol. 

2. Mood Enhancement

Cold water immersion stimulates the release of several mood-boosting neurotransmitters, including endorphins, dopamine, and norepinephrine. These natural chemicals are associated with reward, pleasure, focus and mental clarity, providing a natural mood lift, similar to the effects of exercise.

3. Building Mental Resilience

The discomfort of cold-water exposure forces individuals to confront and manage physical and emotional challenges. By regularly facing the discomfort of cold-water immersion, individuals can develop a greater sense of control over their mental state, which can be beneficial for managing anxiety and improving self-confidence.

4. Reduction in Depression Symptoms

Emerging research suggests that cold water immersion may be a useful tool in reducing symptoms of depression. Cold water activates the Vagus nerve, which is involved in regulating mood via the parasympathetic nervous system. While it may not replace treatment for depression, it offers an accessible, complementary approach to improving mental health by naturally boosting mood-regulating chemicals in the brain.

How to Safely Incorporate Cold Water Immersion

For those interested in trying, it is important to approach the practice safely and gradually. There are general recommendations that we have provided below. It may be worth speaking to your GP first to ensure it is safe, particularly if you have any cardiovascular conditions. 

• Supervision: If you decide to try cold water immersion in natural bodies of water, have someone with you who can stay on land and assist you if necessary. The risk of drowning increases nearly 5 times if the water is below 15 degrees Celsius. 
• Start Gradually: Begin with short cold showers or brief dips in cool water, starting with 20-30 seconds of exposure, and gradually increase the time and intensity as the body adapts.
• Monitor Exposure Time: Avoid prolonged exposure to cold water, especially in extreme temperatures, to prevent risks like hypothermia. After 10 minutes, it can become difficult to swim so make sure you are able to stand or have supervision. 
• Warm Up Slowly: After immersion, warm the body gradually and stay hydrated.

Given that some of the BoDI team have experimented with this type of therapy, we thought it was beneficial to discuss some of our own experiences. 

• Alternating warm and cold – To begin I found finishing my regular shower with the following protocol was when I started to see improvements in my tolerance. I was able to start this protocol earlier in my shower, eventually having reduced the time of the ‘normal’ shower to predominately shower in cold water.
  • Normal shower
  • 20 seconds cold water only
  • 20 seconds hot and cold water 
  • 20 seconds cold water only 
• Personal safety – I found that moving from hot such as a sauna, to the cold water, made me dizzy. I tried this a number of times and the results never varied and hence I stopped moving from extreme heat to extreme cold for safety.

Conclusion

Cold water immersion offers a range of mental health benefits, from reducing stress and anxiety to improving mood and resilience. The physiological responses triggered by cold exposure, such as increased endorphins and improved neurotransmitter balance, can have a lasting positive impact on mental well-being. With regular practice and a gradual approach, cold water immersion can be an effective and accessible method for enhancing both mental and physical health.