Cold exposure therapy has been practiced for centuries and is well-known for its health and longevity benefits. From reducing inflammation and relieving pain to aiding in muscle recovery and promoting weight loss, cold therapy has become increasingly popular among athletes, health enthusiasts, and anyone looking to improve their wellbeing.
Still, for many the promises seem too good to be true. In this comprehensive guide we address any uncertainty by starting with the science before taking you through the cold exposure benefits, methods and how to get started.
What is Cold Exposure?
At its core, cold therapy operates on the principle of hormesis, where the mild stressor of cold prompts the body to reduce heat loss and activate heat generation. The physical response can be felt immediately; from goosebumps to increased heart rates and circulation, it's a symphony of reactions aimed at adapting to the chill.
These responses, collectively known as the cold shock response, include;
Norepinephrine Release: Norepinephrine, a hormone and neurotransmitter, regulates heart rate, thermogenesis, blood vessel constriction, and immune function. Studies show significant norepinephrine increase during cold water immersion of up to 530%, accompanied by a dopamine increase of 250% [1].
Thermogenesis: Thermogenesis is the body's mechanism for producing heat through muscle-shivers and activation of specific cellular processes.
Brown Fat Activation: One of the main ways that ice baths may help with weight loss is by activating brown fat, which is a type of fat tissue that burns calories to produce heat. One study found that brown fat volume increased 45% after exposure to cold for 20 days [2].
Cold Shock Protein Induction: Cold shock proteins help promote cell survival while also aiding brain health through neuronal regeneration.
Mitochondrial Biogenesis: Mitochondrial biogenesis is the creation of new mitochondria which improves aerobic capacity, reduces disease risks and enhances muscle performance. Studies in humans and mice have shown significant impact on mitochondrial biogenesis from cold exposure [3].
Each of the benefits we will cover below draw from a mix of these cold exposure responses for a profound impact on the body.
What are the Benefits of Cold Exposure?
The cold shock response has a profound impact on physiological processes, and over the past few decades numerous studies have been conducted on the potential benefits of cold exposure for health and longevity. While some studies differ in their conclusions, the wealth of evidence speaking for the benefits of cold therapy is signficant.
While the list is long, the 7 most profound benefits are listed below.
#1 Boosted Immune System
Cold therapy has been found to have positive effects on the immune system as it enhances immune function and increases the number of white blood cells, which play a crucial role in fighting infections and cancers.
In one study, participants who took cold showers for 30 to 90 seconds daily for 90 days reported 29% fewer sick days compared to those who didn’t [4].
Another study found that cold water immersion reduced respiratory tract infections by 40% [5].
#2 Metabolic Health and Weight Loss
Cold exposure can have a significant impact on metabolic health. The activation of brown fat increases energy expenditure and promotes weight loss. Unlike white fat, brown fat's activation burns energy, offering solutions to age-related metabolic decline.
One study measured repeated cold exposure 17°C (63°F) for two hours every day for six weeks and saw a thermogenesis increase of 58% compared to baseline levels, coinciding with a loss of roughly 0.7 kg (1.5 pounds) in fat mass [6].
Besides brown fat activation, cold therapy also improves glucose and lipid metabolism, enhances insulin sensitivity, and reduces the risk factors associated with metabolic diseases such as obesity and type 2 diabetes.
Check out our write-up on cold exposure and weight loss for more.
#3 Reduced Inflammation
One of the most notable benefits of cold therapy is its ability to reduce inflammation. Cold exposure reduces inflammation by constricting blood vessels, which reduces blood flow to the inflamed area, in turn reducing swelling and pain. Notably cold exposure has been proven to effectively quell structural inflammation such as arthritis.
Arthritis is an inflammatory degenerative joint disorder that currently does not have a cure, though treatments such as cold exposure can offer pain relief. One study saw decreased production of pro-inflammatory proteins, while another saw significant pain relief of whole-body cryotherapy [7,8].
#4 Enhanced Muscle Recovery
Cold exposure can aid in muscle recovery, also benefiting from the reduction in inflammation as discussed above. Several studies have proven cold exposure to lower inflammation and increase the level of muscle repair-related cytokines.
However, the timing and type of exercise matters as cold exposure immediately following exercise may interfere with the body's hormone balance and limit recovery and adaption [9].
Studies indicate that cold exposure is most effective for resistance (weight) exercise if delayed by an hour or more to not interfere with muscle growth. Endurance (cardio) exercise, however, can see benefits from exposure immediately following exercise.
Check out our write-up on cold therapy's impact on muscle recovery and growth for more.
#5 Pain Relief
Cold therapy is known for its properties in providing temporary relief from acute pain. The cold temperature numbs the affected area, reducing inflammation and pain signals to the brain. The mechanism is much the same as for structural reduction in inflammation.
While cold therapy has proven effective in significantly relieving pain, studies indicate that heat therapy, such as sauna or heat packs, may offer even more profound pain relief [10]. Contrast therapy, switching between heat and cold exposure, has likewise proven more effective than cold therapy alone.
#6 Enhanced Mental Health & Mood
Cold therapy has been reported to have positive effects on mental health, including boosting mood and reducing symptoms of depression and anxiety. The primary mechanisms at work is the release of norepinephrine and dopamine which acts as a mood booster, promoting feelings of alertness and well-being [1].
Multiple studies have hinted at cold therapy’s power in helping more severe mental health issues by reducing the impact of anxiety and depression [11, 12]. This should however not replace professional mental health treatment and should be used as a complementary approach.
#7 Enhanced Cognitive Function
Cold exposure has emerged as a potential ally in promoting brain health. Studies show that the activation of cold shock proteins enables specific proteins crucial for rebuilding synapses, the connections between nerve cells.
A 2023 study published in the journal Nature Medicine found that cold therapy in mice and human cells protected against age-related neurodegenerative diseases such as ALS and Huntington's Disease, by enhancing the body's natural defense against protein build-up [13].
Check out our write-up on cold therapy's impact brain health for more.
What are the Cold Exposure Methods?
There are multiple ways to incorporate cold therapy into your daily routine, depending on your preferences and availability of resources - from cold showers, to cold water immersion (ice baths), to local or whole-body cryotherapy.
Cold Water Immersion (Ice Baths)
Ice baths, also known as cold water immersion therapy or cold plunge, have been a part of wellness practices for centuries. It involves immersing your body, partially or entirely, in cold water at around 5-15°C / 40-60°F for 1-20 minutes.
Cold Showers
Cold showers are a more accessible form of cold therapy that can be easily incorporated into your daily routine. Simply turn the water temperature to the coldest setting - typically it can go no lower than 10°C / 50°F. Typical exposure time should be in the range of 30-90 seconds.
Cryotherapy
Cryotherapy is a modern adaptation of cold therapy that utilizes a cooling chamber, typically less than a couple cubic meters in size, to expose the body to temperatures in the range of -60°-120°C / -140°-248°F for 2-3 minutes at a time. This method often involves the use of liquid nitrogen to create a cryogenic atmosphere.
Which Method is Best?
The good news is that all methods are proven to induce the cold shock response and create the benefits outlined here. But they are not all created equal. While research is generally ambiguous, often conflating different exposure methods, indications are that ice baths is the best method.
To dive more into the topic check out our write-ups on ice baths vs. cold showers and ice baths vs. cryotherapy.
How Do I Start With Cold Exposure Therapy?
If you are convinced about the well-documented benefits, the next step is to start incorporating cold exposure into your routine. For some, heading straight to the ocean or a cryotherapy clinic can be a daunting first step to take.
The good news is you don’t have to rush to the optimal method. Just start slow. While ice baths are arguably the best documented method, it is fine to start with a cold shower for a few seconds each day, gradually building towards longer showers or full water immersion.
No matter your choice here are a few pointers to get you started;
Safety First: Avoid dangerous water and hyperventilation. Start with warmer temperatures and build comfort while you acclimate to cold therapy. Pay attention to your breathing and try to relax your muscles to make the experience more comfortable.
Temperature: For ice baths and cold showers there is no fixed temperature; aim for "really cold but bearable" (around 40-60°F / 5-15°C). For cryotherapy it’s fixed by the clinic.
Start Small, Stay Consistent: Begin with shorter sessions and stick with it; consistency is key for benefits.
Optimal duration & frequency: Gradually build towards the “optimal exposure”
Ice baths: 2-4 sessions of 1-5 mins weekly, totaling 11 minutes.
Cold showers: 30-90 seconds at the end of your morning shower.
Cryotherapy: Standard i 2-3 minutes. 1-5 times per week.
Timing: Morning cold exposure energizes; avoid too close to bedtime.
You can experiment with these cold exposure techniques to find what works best for you. In the end, you don’t have to choose just one. You can both finish every shower with 30 seconds of cold exposure and take an ice bath a few times per week if that is what works.
When you’re ready to optimize your routine and mix it in with other health and longevity routines, head over to our guide to the best cold exposure routines.
Is Cold Therapy Safe for Everyone?
It is always a good idea to consult your physician, especially if you have any pre-existing conditions such as high blood-pressure or heart disease. For the majority however, cold exposure therapy is completely safe when done right.
We talk about the risks, such as hypothermia, after-drop, frostbite and cold shock response in our separate write-up on the dangers of ice baths.
To best counter the risks, it's important to consider safety precautions to avoid getting yourself in harm’s way.
Start Slowly: Begin with short sessions (counting seconds) and gradually increase duration and lower temperature.
Listen to Your Body: Cease the session and seek medical attention if you experience any discomfort like dizziness or chest pain - a little shivering is okay, even beneficial, if manageable
Stay Hydrated: Consume ample fluids before, during, and after the ice bath.
Avoid Prolonged Exposure: Avoid prolonged exposure to extreme cold temperatures without proper supervision.
Avoid Head Dunking: Subersing your head can lead to hypothermia or fainting.
Avoid Solo Sessions: Always have a friend or family member present or join a local winter swimming community.
Summary of Cold Therapy Benefits
Cold exposure triggers a cold shock response in the body to offer a diverse set of health benefits: boosted immune system, improved metabolic health aiding weight loss, reduced inflammation especially for arthritis, enhanced muscle recovery, acute pain relief, improved mental health and mood, and enhanced cognitive function.
If you're ready to take the plunge, check out our review of the best value and premium ice bath tubs currently on the market.
Frequently Asked Questions
How do I start cold therapy?
To start cold therapy, begin gradually with methods like cold showers or ice baths, aiming for "really cold but bearable" temperatures (40-60°F / 5-15°C). Prioritize safety, acclimate slowly, and focus on consistent sessions. Experiment to find what suits you, considering energizing morning exposure and avoiding bedtime sessions. Stay consistent, and feel free to combine techniques for a personalized routine.
How long should I do cold therapy?
Duration depends on which method you choose. For ice baths the recommended duration is 1-5 minutes exposure 2-4 per week. For cold showers 30-90 seconds daily at the back-end of your shower. For cryotherapy a session is typically 2-3 minutes and practitioners have 1-5 sessions per week.
How can I use cold therapy to recover from muscle exercise?
Cold therapy's effects vary with timing and exercise type. Pre-exercise exposure can impair performance, while post-exercise use aids recovery and reduces soreness. It can be helpful in enhancing recovery from cardio or aerobic exercises but research shows that it may hinder muscle growth from resistance exercises.
Are there benefits to sub-zero ice baths?
Research primarily examines above-freezing temperatures. Findings suggest cold immersion affects short-term blood pressure and aids exercise recovery, but specific benefits of sub-zero immersion remain unclear. Further investigation is required to determine any unique advantages.
How can I use cold therapy to lose weight?
Exposing the body to cold activates brown fat, enhancing energy expenditure and insulin sensitivity. Scientific research shows a significant increase in thermogenesis, leading to notable fat loss. This mechanism underscores the potential benefits of incorporating cold exposure for weight management, providing valuable insights into its effectiveness.
Is cold exposure good for crossfit recovery?
Cold exposure can be beneficial for CrossFit recovery,including reducing inflammation, improving blood flow, and alleviating muscle soreness. However, the timing of cold exposure is important, and it is best to delay it for at least an hour after resistance exercise. For endurance exercise, cold water immersion has been shown to be more effective when applied within an hour post-exercise.
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