The Healing Chill: Health benefits of Cold-Water Therapy

_{Written by Dominic Fransen}

What is Cold Water Therapy?

Cold Water Therapy (CWT) is one of the many names to describe intentional exposure to water temperatures below 15℃. It involves resting in a cold body of water such as a bath, tub, ocean, lake, or pool for a short period to activate and improve our body’s natural healing and recovery processes. Practicing immersion into cold water regularly stimulates many health benefits such as increased cardiovascular circulation, reduced muscle inflammation, and weight loss. Typically, CWT is used for muscle recovery purposes after sport or intense exercise but lately many people are realizing its potential in areas such as mindfulness, weight loss, and increased energy to name a few. The duration of time immersed in the water body usually reduces with colder submersion temperatures because of safety factors and risks of dangerous circumstances such as hypothermia.

The Science Behind Cold Exposure

Exposure to cold water below 15 degrees for sustained periods can induce thermal stress to the body which lowers skin and core body temperatures. This thermal stress activates the Sympathetic Nervous System (SNS) triggering the release of neurotransmitters and hormones that drive the stress response. The body’s natural response to dropping temperature is to regulate the imbalance in core temperature by heating the body back to homeostasis (see figure below). Many of the health benefits that result from CWT stem from three key processes: SNS neurochemical release, vasoconstriction & vasodilation, and brown fat activation.

1. Activation of the Sympathetic Nervous System

The cold stimulus activates the SNS resulting in release of the neurochemicals, epinephrine (adrenaline) and norepinephrine (noradrenaline), which are hormones known to increase heart rate, alertness, and energy levels. These neurochemicals work to reallocate resources in the body and trigger physical responses such as the release of endorphins, these are the body’s natural painkillers. This is the point during cold exposure where you feel agitated and feel like you need to move or vocalize to deal with the feeling. 

Healing benefits

2. Vasoconstriction & Vasodilation

Cold exposure forces blood vessels to constrict which reduces blood flow to the body’s extremities by redirecting the flow to vital organs to maintain core body temperature. When you exit the cold water, vasodilation then occurs, causing blood vessels to reopen and improve circulation. This mechanism decreases inflammation by lowering tissue temperature and reducing blood flow to the affected areas which explains why athletes use ice baths after intense workouts to reduce delayed onset muscle soreness (DOMS) therefore speeding up recovery. 

Healing benefits 

3. Increased Production of Brown Fat

Cold water exposure stimulates activation and production of brown adipose tissue (brown fat) which essentially burns calories to generate heat. This increases metabolism as the body has to burn calories to raise the core body temperature. This process is called non-shivering thermogenesis may aid in fat loss and metabolism improvement. 

Healing benefits 

The Health Benefits of CWT

Now we know the science and some of the healing processes associated with prolonged exposure to cold temperatures, we can explore the benefits to our health and wellbeing based on legitimate research. 

Risks and Precautions

• Approach this practice with caution as prolonged exposure to cold water can lead to hypothermia, frostbite, or shock, particularly if the water is below 10°C (50°F) or if the individual has underlying health conditions.
• Beginners should start with short immersion times (1-2 minutes) and gradually increase duration as their body adapts.
• If you have cardiovascular issues, respiratory problems, or chronic illnesses consult a healthcare professional before attempting CWI.

Practical Tips for Getting Started with CWT

Start with Cold Showers: Begin by finishing your regular warm shower with 30 seconds to 1 minute of cold water. Gradually increase the duration as your body adapts.

Try a Cold Plunge Pool: If you have access to a cold plunge pool, start with a few minutes of immersion and work your way up to 10-15 minutes.

Breathe Deeply: Controlled breathing is key to managing the body’s cold shock response. Focus on deep, slow breaths to calm your nervous system during immersion.

Pair with Other Recovery Techniques: Cold water therapy can be paired with other recovery techniques such as stretching, yoga, or meditation to enhance overall wellness.

Listen to Your Body: Always listen to your body’s signals. If you start to feel numb, dizzy, or uncomfortable, exit the water and warm up gradually.

References:

1. Bleakley, C. M., & Davison, G. W. (2010). What is the biochemical and physiological rationale for using cold-water immersion in sports recovery? A systematic review. Journal of Sports Sciences, 28(2), 113-119.
2. Leeder, J., Gissane, C., van Someren, K., Gregson, W., & Howatson, G. (2012). Cold water immersion and recovery from strenuous exercise: a meta-analysis. American Journal of Sports Medicine, 40(7), 1835-1840.
3. Buijze, G. A., Sierevelt, I. N., van der Heijden, B. C., et al. (2016). The Effect of Cold Exposure Training on Health and Immune Function: A Randomized Controlled Trial. PLOS One, 11(12), e0167410.
4. van der Lans, A. A., Hoeks, J., Brans, B., et al. (2013). Cold acclimation recruits human brown fat and increases nonshivering thermogenesis. Journal of Clinical Investigation, 123(8), 3395-3403.
5. Shevchuk, N. A. (2008). Adapted cold shower as a potential treatment for depression. Medical Hypotheses, 70(5), 995-1001.
6. Słomko, J., et al. (2015). Cold-induced enhancement of testosterone production in aging males. Rejuvenation Research, 18(3), 221-225.
7. Cold Water Immersion (scienceforsport.com)
8. Cold Water Immersion (CWI) | Wim Hof Method
9. The Science & Use of Cold Exposure for Health & Performance – Huberman Lab – Huberman Lab