Wim Hof says: “the cold is merciless, but righteous”, and I think this encapsulates what those of us who have discovered the benefits of cold water immersion have come to understand. Submerging yourself in icy water doesn’t really get easier, or at least the cold doesn’t show any sympathy for how you’re feeling that day, but it has a profound effect on our body and mind every time you take the plunge.

Taking an ice bath is the act of getting into a cold body of water (an ice tub or even a lake if you have one handy) and immersing your body for a period of time in order to reap a potential huge variety of cold plunge benefits, which we'll explore in this article.

Cold water immersion is great for a number of things. If you just want the headlines check out our top 5 benefits below. However if you want to dive deeper, we’ll break down each of these headlines within the article:

• Top 5 ice bath benefits
• Physical benefits of ice baths
• Mental benefits of ice baths

Top 5 benefits of ice baths

Improved muscle recovery and reduced soreness

Some 2022 research shows that cold water immersion can lead to reduced muscle soreness after intense workouts or endurance training, quicker recovery, and benefits to muscle power. It should however be noted that it’s best to wait at least 4 hours after strength training before getting into your ice bath or you might see limited gains.  

Reduced anxiety and better sleep

Taking ice baths activates your vagus nerve, which is essentially in charge of our ‘fight or flight’ response. Cold water exposure tells the vagus nerve to slow down our breathing and heart rate which in turn puts us into a ‘parasympathetic state’; one of reduced anxiety and relaxation. This has great stress reduction implications and in turn can help with sleep quality.

Improved immune system

Sick of getting sick? Cold water immersion might actually be able to help with that. This study in the Netherlands showed a 30% reduction in people calling in sick for work after cold exposure.

One study even suggested that cold water could help the body in being more resistant to certain types of cancer.

Better circulation and heart health

When you immerse yourself in cold water your body immediately gets the signal to start warming up. This means your heart starts pumping blood around your body to protect the vital organs but at the same time it constricts the blood flow near your skin. By doing this regularly it's almost like a workout for your circulatory system.

Reduced inflammation

This one might sound straight-forward but getting into the cold causes your blood vessels to constrict and your muscle tissue temperature is reduced. This means that less swelling occurs in damaged areas (it’s actually why we put ice packs on injuries), which can be good for recovery or even things like joint pain. Reduced inflammation is something of a hot topic recently, and can lead to a wide variety of negative outcomes so people are searching for ways to fight it - cold water immersion can be a powerful tool for this.

Physical benefits of ice baths

Lots of things happen when you expose yourself to icy water. We’re going to talk through the many different reactions and benefits that occur, being sure to cite studies that back up any claims along the way.

Metabolism/weight loss

Cold water immersion can increase your metabolism and lead to weight loss. Yet another weight loss gimmick? Actually, no. While there isn’t a huge amount of scientific studies on this benefit, there are some really promising and intriguing results in what has been done.

One interesting study was done on a group of Korean divers who made their living off diving for seafood in the 50°F to 70°F (10°C to 25°C) waters surrounding Jeju Island. This group of people first caught attention for their incredible resilience to the icy water while only wearing thin cotton bathing suits. The study found that when they dove during winter with the colder waters, their base metabolic rate was significantly higher than in summer months, meaning they would burn calories faster.

Another study showed that when people submerged themselves in water colder than 59°F (15°C) for about 5 minutes it led to an increase in metabolism. It’s even been shown to increase metabolism by 350% at this temperature.

It should be stressed that more research needs to be done here before anything can be definitively concluded, but it does lead into another benefit that’s somewhat related: generation of brown fat.

Brown fat generation

Brown fat makes up a small percentage of the fat that exists in our bodies, the majority is made up of white fat. The main difference between the two (apart from their colour) is the fact that brown fat contains a high level of iron-rich mitochondria, which makes it way more metabolically active. 

What does this mean and why should we care about this? White fat keeps your organs warm by literally insulating them, and it takes up a lot more space than brown fat does. Brown fat, however, keeps the body warm by burning energy (this is called thermogenesis) and creating heat. At the same time it burns calories and also takes up less space. It’s recently been touted as a potential remedy for obesity and other metabolic issues.

Another interesting aspect of brown fat is that a study found that people with higher levels of brown fat activity had less BCAAs (branched chain amino acids) in their bloodstream when they were exposed to cold temperatures. BCAAs are important for our bodies but high levels of them have been linked to obesity, diabetes, and insulin resistance.

Exposing yourself to cold temperatures has been suggested to promote the generation of brown fat. One study showed that after a month of exposure to mild cold, brown fat volumes rose by 42% in participants indicating that maybe the more people are exposed the more the body generates brown fat.

Improving circulation

When you get into an ice bath, one of the first things that happens is that your body gets a shock. All the signals are being sent to the brain to say that you’re just about to get significantly colder, and fast. The body then goes into survival mode and starts to pump blood to your internal organs to protect them, and your veins constrict slowing blood flow to your extremities.

Once you emerge from the cold water your body then pumps blood back out to the rest of your body, and your veins relax and open up again. It’s almost like your entire cardiovascular system is flexing and relaxing again like a muscle.

When this happens your whole body gets oxygenated, waste products get flushed out from your bloodstream and your skin even gets a nice glow.

Skin and hair

Another intriguing thing that happens when you get into cold water is that your skin and hair will benefit. It's actually a fairly straightforward reaction; your skin will get the circulation and oxygenation benefits we mentioned in the section above, but also your pores will be discouraged from opening up due to the cold. This means that puffiness will be reduced and certain oils that are good for keeping your skin moisturised will be accumulated.

As for your hair, the cold water will “flatten the ruffled cuticles and lock in moisture to prevent breakage” and will also generally close up your pores on your scalp allowing for less dirt and grime to get inside. Be warned though, too much cold on your hair will make your hair flat and will remove some of its volume.

Immune system

We talked above about the Dutch study that led to a 30% reduction in people calling in sick to work after being exposed to cold, and even about the potential protection against certain cancers.

There’s a now famous study done with Wim Hof and some people he trained that essentially showed that when people use cold water immersion, breathing exercises, and meditation to fight illness they see pretty amazing results. Both the control and test group were injected with a bacteria and the group who had done cold bathing suffered fewer symptoms and their bodies generated less pro-inflammatory cytokines and more anti-inflammatory chemicals to respond to the bacterial infection.

Remember these results are certainly positive but there’s no need to overdo it. In the Dutch study they found that the length of the exposure didn’t necessarily lead to more protection - so it’s probably the initial shock the body experienced that drove the strong results.

Lymphatic system

The benefits to your lymphatic system is one of the reasons why your immune system might be boosted by cold therapy. Your lymphatic system is vital for cleansing the body of unwanted waste and buildup, and is actually a part of your wider immune system.

Its job is to keep body fluid levels in balance in order to fight infections, by draining ‘lymph fluid’ back into the blood stream via lymph nodes.

The whole system depends on muscle contraction to move this fluid around the body, and in this study they found that cold temperatures significantly improved lymph flow. Cold water makes the lymph vessels contract, and therefore better at moving lymph fluid.

Lung function

What’s the first thing that happens to you when you submerge yourself in an ice bath? You lose your breath and are forced to focus entirely on your breathing.

I guess it’s no surprise that this has been shown to be really beneficial for your lung function. When you’re hit by that feeling of breathlessness it means your lungs are forced to work harder and blood flows to your internal organs to heat them up, both of which affect the flow of oxygen and overall well being of your lungs.

Stabilises blood sugar levels / insulin

 

Cold water exposure has recently started gaining a lot of interest in the diabetic community. Studies like this one are linking cold water to increases in insulin sensitivity through the increase in a hormone called adiponectin, which helps your body with insulin resistance and inflammation.

Broadly speaking there’s somewhat of an epidemic in insulin resistance in modern society, some people believe it’s a major cause of a wide variety of diseases and illnesses. At the very least insulin resistance is a culprit in development of type 2 diabetes, and there is really promising research being done around the positive effects of cold water on preventing and even reversing these conditions.

Chronic medical conditions and pain

A lot of people suffer from autoimmune conditions, which a lot of the time come with chronic inflammation. This inflammation can cause great pain in joints, redness and swelling, digestive issues and many more negative symptoms. Cold water immersion can be a great tool to help alleviate discomfort with conditions like these due to the nature of its inflammation reducing effects.

This study is a perfect example, with people in Indonesia who suffered from arthritis experiencing life changing benefits using cold water therapy. 76 people participated and half of them spent 20 minutes per day for 4 weeks in 20°C - 30°C water. The test group experienced significant pain reduction, improved joint mobility, better ability to engage in physical activity, reduced stress, reduced anxiety and better overall quality of life.

There are a wide variety of chronic medical conditions that are being subject to studies with cold water therapy and are seeing fantastic results.

Fertility in men

When men get into freezing cold water they might be cautious about what happens downstairs and if it's dangerous for sexual health in any way.

 

Thankfully it’s unlikely to be dangerous, though there isn’t any definitive evidence that it’s actually beneficial. There’s a longstanding myth that cold water exposure increases testosterone but sadly this is unlikely to be the case. This study found that testosterone levels increased during exercise but then decreased in cold water exposure after the exercise. This one showed no change in testosterone levels at all.

Now that's testosterone, but there is evidence pointing to the fact that cold water exposure does in fact improve both sperm quality and volume. So in reality despite not directly increasing testosterone levels one could argue the benefits to sperm can absolutely help with fertility issues, generally speaking.

Mental benefits of ice baths

Getting into a body of cold water clearly has a wide variety of effects on your body in the physical sense, however there are some incredibly powerful mental effects that also occur.

Mental health, depression, anxiety

One of the most exciting use cases for cold water exposure is its potential to alleviate depression, anxiety, and even PTSD. There is a lot of anecdotal evidence for this, but data is starting to emerge backing up these claims. 

 

For example: depression has been associated with increased inflammation in the body, and a reduction in inflammation also with reduced depression. It’s been established already that cold water reduces inflammation in the body, so it would make sense that some people have experienced less depression and anxiety after and during ice bath sessions.

There was an interesting experiment where a 24-year old woman with severe depression, who didn’t respond to any medications, was prescribed a weekly cold water swim. Her symptoms improved dramatically and a year later when they checked in on her she was continuing to swim and was medication-free.

Another piece of the puzzle is the stimulation of the vagus nerve, as we discussed above, which happens even with a small exposure to cold water such as splashing your face. What happens when the vagus nerve is activated is that your body is pushed into a ‘parasympathetic state’ (also known as rest and digest, the opposite of fight or flight) which slows down your breathing and heart rate. This could indeed lead to feelings of calm and relaxation.

Hormones also most certainly play a role here. When you get into cold water your body immediately releases a variety of mood-elevating hormones such as dopamine, beta-endorphins, adrenaline and noradrenaline leading to feelings of excitement and mental stimulation. The cold actually causes the levels of these hormones to stay elevated for a while, and their continuing effect increases levels of energy and focus for hours after your bath.

Resilience and grit

Grit can be defined as the firmness of mind or spirit. The Finnish have a good word for it: Sisu, which means stoic determination or tenacity of purpose. It’s a trait they are proud to embody. Is it a coincidence it’s so cold in Finland? Maybe.

We all have things we don’t want to do on a daily basis, but building up the mentality to do them anyway because we know they’re good for us can be a challenge and it’s definitely a skill to be learned.

When you force yourself to submerge your body in icy cold water on a regular basis you’re flexing this mental muscle and building grit. Andrew Huberman says that when you do this you’re exerting ‘top-down control’ over deeper brain centers, the ones that plan and suppress impulsivity. What’s really important about taking control here is that you can carry this skill over to other situations. It means you’re going to be more equipped to cope better and maintain calm when you’re faced with real world stressors.

Ice baths are a fantastic tool for both the mind and the body. You can practice cold water exposure to help with conditions you might be suffering from, for general longevity, or even to steel your mind.

It’s important, however, to know your limits and listen to your body. So while we have explored a wide variety of benefits ice baths can bring, we urge you to take things slow and gradually build up the amount of time you spend and the temperatures you use when exposing yourself to cold. If you are ever unsure, please speak to a medical professional before braving the ice.