You know how you ice injuries? Let’s say your legs are killing you from running. Maybe you are a pitcher and your arm is throbbing.
The first thing you normally do is ice that part of your body.
Well if icing one part of your body can help you heal, what can happen when you ice your entire body?
Putting your body through extreme temperatures, in a controlled setting, can do wonders for your health. Cold exposure benefits your body, and not only that, but it directly impacts your mind.
It is science-based when we say cold exposure helps your mind, body, and spirit. Not voodoo logic.
What is cold exposure?
In this context, cold exposure is either some form of cold-water immersion or cryotherapy.
Cold-water immersion can be an ice bath, cold shower, a cold swim. It uses water as the medium. Cryotherapy uses liquid nitrogen to freeze your whole body or a localized part of the body.
There are some differences in modality and temperature, covered here, but each has its benefits. The terms are used interchangeably.
Cold exposure benefits
- Stronger immune system
- Better stress response
- Decrease inflammation
- Physical recovery
- Weight loss
- Energy & focus
- Improve mood
- Helps fight depression
- Discipline & resilience
Stronger immune system
The immune system is an important defense mechanism that protects our bodies against viruses, bacteria, and other pathogens that cause disease.
You get sick when your immune system is weak or overactive, so a healthy immune system is essential to fight off diseases.
White blood cells are key players in our immune system. These white blood cells fight off bacteria, viruses, parasites, and fungi. Coldwater immersion increases the number of white cells in your body, including lymphocytes.
There are three main types of lymphocytes. B cells produce antibodies to fight invading antigens. T cells destroy the body’s own damaged cells that could become cancerous. Natural killer cells specialize in killing cancer and virus-infected cells.1
Your immune system benefits from cold water immersion because a cold plunge increases the amount of these immune-boosting cells. 2
This can explain why winter swimmers have higher numbers of white blood cells compared to nonhabitual winter swimmers. They epidemiologically have a 40% decrease in respiratory tract infections incidences, demonstrating their strong immune system.3
Wim Hof uses cold therapy to strengthen his immune system
Wim Hof is another example of the benefits of cold exposure for one’s immune system. He can control his immune system and stress response by practicing cold exposure and breathwork.
“The Iceman” is known for his ability to withstand freezing temperatures. He is a world record holder with the furthest swim under ice, fastest half marathon barefoot on ice and snow, has set the world record for full-body contact with ice a total of 16 times, and climbed Mount Everest in just shorts and shoes (up to 23,600 ft).
Wim has become a test subject since touting the benefits of cold exposure and teaching his Wim Hof Method.
He was even injected with e.coli in a study to demonstrate his ability to control his immune system. He fought it off with his immune response, practicing meditation and concentration, which he uses during his cold exposure.4
“These results are definitely remarkable”, commented the researchers.
Another group of researchers in The Netherlands found that “The concentration/meditation technique used by this particular individual seems to evoke a controlled stress response. This response is characterized by sympathetic nervous system activation and subsequent catecholamine/cortisol release, which seems to attenuate the innate immune response.”5
He has built up his immunity by habitually doing cold exposure. The studies also mentioned his ability to control a stress response…
Improve stress response
Managing stress is a critical part of our daily lives because chronic stress is detrimental to our health. Negative stress, called distress, can be both the result of and result in inadequate sleep, anxiety, poor gut health, and lead to diseases.
You can get stressed from traffic jams, being late, or having an argument with a loved one. An unhealthy diet, lack of sleep, and even recurring negative thoughts all increase stress on your body as well.
But stress can be good, known as eustress. The right amount of eustress can make you more resilient. This includes activities like exercising, heat stress like sauna use, fasting, and cold stress.
When you dip into a cold plunge, your body triggers the autonomic nervous system. This system is a network of vessels and nerves, split into two parts that control your response to stress.
The first part, the sympathetic nervous system, triggers your “fight or flight” response. The second part is the parasympathetic nervous system, which is more restorative and helps to shut it down once the stress has passed.
Cold exposure increases stimulation of the vagus nerve. While your body adjusts to the cold, sympathetic activity declines, while parasympathetic activity increases.
You can practice taking yourself from a fight-or-flight response in the cold to a parasympathetic one of calm.
Daily cold exposure benefits you because you can better handle stress in other areas of your life. When you manage your stress response, fewer things make you angry, you are happier, and you can really control your relaxation to improve sleep.
The purpose of inflammation is to protect and heal. Your body does this by eliminating the initial cause of cell injury, clearing out dead and damaged cells, and repairing itself.
We suffer from chronic inflammation when this process runs awry. A key driver in the aging process is chronic inflammation. Chronic inflammation is associated with most age-related diseases.
On the contrary, low inflammation is the only biomarker that predicted survival and cognitive capabilities across all age groups.
So how do you benefit from cold exposure?
Cold exposure leads to a dramatic increase in norepinephrine, which is a naturally occurring stress hormone and neurotransmitter in your body. It is released in your body when a stressful event occurs, like jumping into a cold plunge.
Norepinephrine decreases inflammation, thus reducing pain in the process.
An example of this is in a randomized controlled trial involving patients with arthritis. Arthritis is an inflammatory degenerative joint disorder that is painful and reduces mobility.
In the study, patients with arthritis who underwent wholebody cryotherapy 3x per week had a significant reduction in pain. Local cryotherapy, cooling just the affected tissue, was also shown to reduce pain.6
Athletes have used cold water therapy to recover for years to recover from training.
The inflammation that occurs immediately after exercise is necessary to activate genetic pathways that contribute to creating more mitochondria and muscle growth.
Peak inflammation from exercise is about an hour after. Therefore, you want to wait until at least an hour after exercise to get the benefits of cold exposure.
Whole-body cryotherapy done 1 hour after exercise has shown improvements in a variety of performance measures, like power and recovery.7
Elite runners that engaged in whole body cryotherapy 1 hour, 24 hours, or 48 hours post hill sprint running had a 20% increase in speed and power up to two days later.8
Inflammation that is too high postexercise can result in performance deterioration and muscle damage. This is problematic for training several days later because there is a greater risk of injury due to soreness, changes in muscle function, and the inability to achieve peak performance.
Elite runners significantly enhanced muscle recovery and decreased inflammation by engaging in whole-body cryotherapy. The runners did just 3 minutes of cryotherapy at both 1-hour and 24 hours postexercise. 9
Similar performance enhancements were shown in elite tennis players. The tennis players that engaged in whole-body cryotherapy twice a day (in the morning and evening while training in the afternoon) for five days had a 2.5x decrease in the potent proinflammatory cytokine TNFalpha and a 23% increase in the cytokine IL6, which has both pro and antiinflammatory properties and plays a role in muscle repair.10
These professional tennis players also experienced a 4% increase in “stroke effectiveness,” meaning they hit more balls in the target zone compared to the players that did not do cryotherapy.
This is interesting because sports are a game of inches. Just the slightest improvements make all the difference. This stroke effectiveness could be from a number of factors, such as norepinephrine improving focus combined with optimally performing muscles.
These athletic performance benefits from cold exposure may also be sustained over a prolonged time period.
Elite cyclists engaged in 15 minutes of coldwater immersion 59.5°F for 30 minutes posttraining 4 times per week. This training lasted 39 days, consisting of a mixture of low–moderateintensity road rides and highintensity interval sessions on an exercise bike.
The cyclists that engaged in coldwater immersion posttraining experienced a 4.4% increase in average sprint power, a 3% enhancement in repeat cycling performance, and a 2.7% increased power over the 39 day training period.11
Cold exposure can burn fat
Cold exposure is an effective tool for people who are looking to lose a few pounds.
Research has shown that cold water immersion increases metabolism and stimulates the generation of brown fat. Brown fat is a specific type of fat tissue that in turn generates energy by burning calories.
Brown adipose tissue (brown fat) is a dark-colored tissue that is linked to the rapid generation of heat. While white fat stores energy, brown fat uses energy.
This brown adipose tissue burns calories to keep warm, as they are unable to shiver.
Adults usually have significantly lower levels of brown fat compared to babies and teenagers. The brown tissue is replaced by white tissue, instead, which makes us fat. Activating brown adipose in adults could result in significant health benefits.
Controlled exposure to cold, is associated with brown fat activation. Once you are more practiced, you develop brown fat. This is an efficient source to regulate body heat. You have to use it, otherwise, you lose it.
Further along the line, you will get more adaptive towards the cold, your body and mind will get more cold-conditioned and you can generate heat through top-down processes
One of the body’s ways of responding to cold is to increase metabolism to warm the body and, in the process, burn fat. Cold thermogenesis is this process.
There are two types of thermogenesis that occur as a biological response to cold exposure. The first kind of cold-induced thermogenesis occurs in muscle tissue and involves ramping up the metabolism in order to produce heat. This works because metabolism is not 100% efficient and produces heat as a byproduct. This is referred to as shivering thermogenesis because the muscle contractions are what actually increase the energy metabolism.
The second type of cold-induced thermogenesis occurs in adipose tissue (fat) and does not involve shivering… Nonshivering thermogenesis. This type of thermogenesis is what is really responsible for the “fat-burning” effect that cold exposure can have and usually happens after the body has adapted to cold exposure.
Cold exposure essentially increases your metabolism by producing more mitochondria in adipose tissue, leading to a browning effect. The more brown adipose tissue your body has, the more fat your body will burn.
It is called brown adipose tissue because each fat cell has more mitochondria per cell. The mitochondria make the fat appear brown when looking at it under a microscope.
So cold exposure will increase brown adipose tissue and having more brown adipose tissue increases your metabolism.
One study done in a small group of young men showed that coldwater immersion in 68°F for one hour increased metabolic rate by 93% and 1 hour at 57°F increased metabolic rate by 350%. 12
Cold exposure gives you energy & focus
Everybody has their own method for waking up; double shots of espresso, a workout, meditation, and so on. A round of cold exposure can be a jump start to your morning or need an afternoon pick-me-up without needing caffeine.
Plunging into cold water triggers the production of the neurotransmitter norepinephrine, as mentioned. It is a critical chemical in the body that along with reducing pain, helps regulate attention, focus, and energy.
A daily cold plunge can help increase your levels of norepinephrine, simultaneously increasing your energy.
Treatments of ADHD are stimulants that increase dopamine, norepinephrine, adrenaline. Cold exposure increases all of these.
In cold, you increase vasoconstriction of blood flow to the brain. But after you warm-up, you get this big rush in blood flow to the brain. This leads to an increase in norepinephrine neurotransmission in your brain to improve focus, cognitive ability, energy, and mood.
A cold plunge improves your mood
Cold exposure induces a robust release in both dopamine and norepinephrine, as you know by now.
Dopamine is a type of neurotransmitter that your body makes, and your nervous system uses it to send messages between nerve cells. It directly impacts how you feel, your motivation and drive, pleasure, and craving.
The previously mentioned study of a small group of men found that doing cold water immersion led to a 2.5x increase in dopamine levels. That’s even more than sex! 13
This high dopamine level is similar to the rush of dopamine that you get with cocaine. The difference is cocaine has a big rush of dopamine, followed by a crash.
A cold plunge is a more sustainable release of dopamine, for up to around 3 hours.
Dopamine and norepinephrine are closely related. Dopamine is converted into norepinephrine, which is converted into adrenaline.
It also may help with depression
We’ve talked about norepinephrine’s impact on making your body feel better and improving your focus and energy. Researchers have found that it may help with our moods because there is more and more evidence that a lack of norepinephrine can contribute to depression.
Low norepinephrine levels lead to inattention, poor mood, low energy, and cognitive ability. This suggests that a cold plunge may help to reduce depression and improve overall mood.
Cold water is expected to send an overwhelming amount of electrical impulses from peripheral nerve endings to the brain. This can have an anti-depressive effect. Likely due to the high density of cold receptors in your skin.14
A longterm study in humans directly compared people that immersed themselves in cold water at 40°F for 20 seconds to those that did whole body cryotherapy for 2 minutes at -166°F three times a week for 12 weeks.
The results showed that in both cases, norepinephrine increased 2-3x. 15 This release of norepinephrine didn’t seem to be reduced with habituation to cold.
Another study showed that participants doing coldwater immersion for 1 hour at 57°F increased their norepinephrine levels by 530% and also increased dopamine by 250%.16
A cold plunge has a similar anti-depressive effect on your body as exercise, especially considering the increase in dopamine, norepinephrine, and endorphins.
You get the mood-boosting benefits of those chemicals, handle stress, plus you are overcoming an obstacle or a challenge, This can increase your resilience and discipline, and fight off depression.
Improved brain function
Not only can a cold plunge help with your mood, but it also improves your brain function. A recent study showed a decrease in the risk of depression, dementia, and Alzheimer’s in people who regularly swim in cold water.17
The link between dementia and Alzheimer’s lies in the destruction and creation of synapses, which are the connections between cells in the brain. The loss of these connections leads to memory loss, confusion, mood swings, and the eventual death of the cell.
Losing synapses occur with normal brain aging. Neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease and as well as traumatic brain injury, accelerate the loss.
The ability to protect synapses effectively might have huge implications for Alzheimer’s disease, dementia, other neurodegenerative diseases, and aging.
The theory with brain synapses and cold exposure stem from hibernating animals. For example, bears lose these connections during hibernation, but they regenerate in spring when the animal awakens.
Humans have these cold-shock proteins that are also in these hibernating animals. Inducing a controlled state of hypothermia has often been used to help people recover from cardiac procedures and head injuries. Cooling the body can slow the destruction of cells and protect synapses.
This process of controlled hypothermia induces cold-shock proteins, which helps contribute to synapse regeneration when the body gets back to a normal temperature.
Can cold exposure help with concussions?
There has been some preliminary research showing that cooling your head after a concussion can be a possible treatment. Often people with concussions have an excess of CO2 in their brain because the vagus nerve isn’t working properly. Sitting in an ice bath or dunking your head in cold water speeds up and slows down the vagus nerve. This essentially helps it work better.
Ben Greenfield recommends cold exposure for concussions in his podcast episode 402.18 Cold thermogenesis, dunking your head in cold water, or a cold shower can help stimulate the healing of the blood-brain barrier with the improved cardiovascular flow.
More research needs to be done on this topic. What we know now is promising.
Be more discipline and resilient with a cold plunge
It can be difficult to make that first plunge into an ice-cold tub, but the payoff is amazing.
A quick cold plunge every day can push the limits of your mind, just like an intense workout pushes the limits of your body. It becomes easier to do it when it is habitual.
Many cold plungers talk about how their mind tells them that they don’t need to cold plunge that day. They can just do it tomorrow.
You build up that discipline each day you return to that cold plunge, disregarding what your mind tells you. It takes a strong mind to endure the cold over and over again.
A lot of us eventually find ourselves craving that icy rush of energy.
Willpower can be trained just like a muscle. Sure, some people naturally have more willpower than others, just like any other characteristic. That is no excuse for not improving what you are capable of.
Incorporating cold exposure into your daily routine strengthens your willpower, which has benefits in other areas of your life.
People with low willpower tend to make poor choices in life because they give in to short-term temptations at the expense of longer-term goals. People with more willpower are happier, healthier, more satisfied in relationships, and have better careers. They can cope with stress, conflicts, and adversities more easily.
Frequent cold exposure can activate potent antioxidants, more than taking supplements.
For example, young men exposed to cryotherapy for 3 minutes at -202°F every day for 20 days doubled the activity of one of the most potent antioxidant enzyme systems in the body called glutathione reductase. There was also an increase in another potent antioxidant enzyme called superoxide dismutase by ~43%. 19
Similarly, elite kayakers that engaged in whole-body cryotherapy (248 to 284°F or 120 to 140°C) 3 minutes a day for 10 days increased the activity of superoxide dismutase by 36% and glutathione peroxidase by 68%.20
Superoxide dismutase is an enzyme is in your mitochondria that cleans up all that damage that is being produced every second of every day.
- Immune system of cold-exposed and cold-adapted humans
- Adaptation related to cytokines in man: effects of regular swimming in ice-cold water, Winter swimming: healthy or hazardous?: Evidence and hypotheses
- Research on ‘Iceman’ Wim Hof suggests it may be possible to influence autonomic nervous system and immune response
- The influence of concentration/meditation on autonomic nervous system activity and the innate immune response: a case study
- Effectiveness of different cryotherapies on pain and disease activity in active rheumatoid arthritis. A randomised single blinded controlled trial
- Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training
- Effects of Whole-Body Cryotherapy vs. Far-Infrared vs. Passive Modalities on Recovery from Exercise-Induced Muscle Damage in Highly-Trained Runners
- Time-Course of Changes in Inflammatory Response after Whole-Body Cryotherapy Multi Exposures following Severe Exercise
- Five-Day Whole-Body Cryostimulation, Blood Inflammatory Markers, and Performance in High-Ranking Professional Tennis Players
- Does hydrotherapy help or hinder adaptation to training in competitive cyclists?
- Human physiological responses to immersion into water of different temperatures
- Human physiological responses to immersion into water of different temperatures, Controlling Your Dopamine For Motivation, Focus, & Satisfaction
- Adapted cold shower as a potential treatment for depression
- Effects of long‐term whole‐body cold exposures
- Human physiological responses to immersion into water of different temperatures
- Cold Water Swimming—Benefits and Risks: A Narrative Review
- Concussions: A Must-Listen Podcast If You Or A Loved One Have Ever Had A Head Injury
- Whole-Body Cryostimulation – Potential Beneficial Treatment for Improving Antioxidant Capacity in Healthy Men – Significance of the Number of Sessions
- The effect of whole-body cryostimulation on the prooxidant–antioxidant balance in blood of elite kayakers after training