A growing number of athletes, trainers, celebrities and wellness influencers are espousing the use of cold-water immersion therapy. But what is it, how do you do it properly and can it really be of benefit to our health?

When practiced on a regular basis, cold water immersion therapy can provide long-lasting changes to your body’s immune, lymphatic, circulatory systems that enhance the overall quality of your life. [1]

Find out more about how it can benefit you.

What exactly is cold water immersion therapy?

Also known as cold hydrotherapy, cold water immersion therapy is the practice of using water that’s around 15°C and often lower to treat health conditions or stimulate health benefits.

Although people have been practicing it for centuries, in recent times, people have adapted the practice to suit their lives whilst still reaping the benefits. Commonly used methods include ice baths, brisk daily showers, outdoor swims and cold-water immersion therapy sessions.

What are the origins of cold-water immersion therapy?

Cold water immersion is an ancient practice that has roots in many different cultures, particularly those in high latitudes. People living in cold climates like Scandinavia, Japan, Russia and Canada have been practising cold water therapy for centuries

Scandinavians, in particular, have long practiced a dip in extremely cold water after a sauna to eliminate the body from toxins, get the blood flowing and to release endorphins.

It’s also documented that Hippocrates and Thomas Jefferson saw the benefits of soaking in cold water. “Hippocrates’ water therapy was designed to allay “lassitude” (physical or mental weariness), while Thomas Jefferson claimed that 60 years of daily cold foot baths every morning had “maintained his good health”.” [2]

What are the benefits of cold-water immersion?

There has been much research that has investigated the benefits of cold-water immersion therapy. These studies point to wide-ranging benefits from the practice, some of which require more investigation to be conclusive.

One study reported a number of benefits to regular winter swimming. These included significantly decreased tension, fatigue, memory, and mood negative state points with the duration of swimming period; significantly increased vigour-activity scores; relieved pain who suffered from rheumatism, fibromyalgia, or asthma; and improved general well-being in swimmers. [3]

Cold water immersion therapy can give you a better quality, deeper sleep at night-time and also boost your energy levels during the day, making you feel more vital and equipped to deal with whatever comes your way.

Other benefits of cold-water therapy include:

Reduced muscle soreness and reduced inflammation

Cold can help to numb pain by constricting blood vessels, which in turn reduces blood flow which helps reduce swelling and inflammation. It can also numb the nerve endings which can relieve pain.

Several studies have shown that cold water immersion therapy helps to counteract side effects of inflammation and muscle soreness after working out. In addition, a few studies demonstrated athletes and cyclists reported reduced muscle soreness after practicing cold water therapy.

Faster cool down

A review of 19 studies concluded that cold water therapy is much more effective in cooling the body down faster than just being in a cool environment. It’s important that you immerse your whole body for this to be effective.

Boosted immune system

There is evidence that cold water therapy can stimulate your body’s immune system which helps you to fight illness.

Several studies have demonstrated this including one which found that meditation, deep breathing and cold-water immersion techniques improve immune function. In another study, in which participants were exposed to a bacterial infection, those practicing cold water immersion therapy displayed fewer symptoms than the control group. Their bodies produced more anti-inflammatory chemicals and fewer pro-inflammatory cytokines in response to the infection. [4]

One study found that people who take cold showers are 29% less likely to call in sick for work or school. The study enrolled 3,018 people who took a hot shower then used applications of cold water for 30–90 seconds based on their research group. One research group took warm showers as usual and did not use cold water at all.

Although those who took cold showers were less likely to call in sick for work, they did not report fewer sick days. The researchers concluded that cold showers might make a person’s illness feel less severe, allowing them to continue with their daily activities.

They did not find a difference between the people who took a cold shower for 30, 60, or 90 seconds. This led them to conclude that cold water triggers the body’s immune system regardless of duration. [5]

Improve circulation

Cold water immersion therapy can stimulate blood flow, just as exercise and a healthy diet do.

Cold exposure (CE) to small surface area produces compensatory vasodilatation deeper in the vascular system resulting increased blood flow to the tissues underlying the site of exposure. This vascular reaction occurs mainly to maintain constant deep tissue temperature. [6]

When your heart is forced to pump more efficiently, it pushes blood through all your vessels and supplies every part of your body with oxygen and nutrients.

Improve metabolic function

More research is needed, but there is some evidence that demonstrates that cold water immersion therapy can increase your metabolic rate, helping you to burn calories and aid weight loss. Cold water also increases the body’s metabolism because it has to work harder to maintain a stable temperature.

Improved mood and help to build resilience to stress

Although cold water therapy is not a cure for depression and anxiety, studies have shown that taking cold showers for twice a day improves mood, make you feel more energetic and vital.

Exposure to cold is known to activate the sympathetic nervous system and increase the blood level of beta-endorphin and noradrenaline and to increase synaptic release of noradrenaline in the brain as well. Additionally, due to the high density of cold receptors in the skin, a cold shower is expected to send an overwhelming amount of electrical impulses from peripheral nerve endings to the brain, which could result in an anti-depressive effect. [7]

Research tells us that cold water therapy may lower cortisol levels too. Cortisol is the “fight-or-flight” hormone that the body releases in response to stress. Lowering cortisol levels in the blood may therefore help reduce stress levels.

More research is required to confirm this benefit.

Improved skin and hair

Cold water helps to reduce the size of your pores and tightens your skin. Warm water releases the oils from your skin and hair but cold water will help you hold onto to those precious oils, keeping both your hair and skin moisturised and healthy.

How to practice cold water immersion properly

The water must be below 15 degrees Celsius. Some people brave just a few degrees although this isn’t recommended when you are just starting out.

Plunging into an ice bath, the lake or the ocean. Best way is to start with taking cold showers at home.

After you have showered at your normal temperature, remain under the water.
In slow intervals, turn the temperature down to make the water colder.
Each time the temperature drops you should feel uncomfortable, then comfortable again, relatively quickly.
The aim is to get to the temperature where the uncomfortable feeling lasts and doesn’t subside. This is when the benefits can occur.
Try and hold out for as long as you can and no longer than a few minutes on your first go, aiming for no more than 5 minutes, eventually. This may take a few showers before you can last that long. [8]

You can also start by taking a warm shower and then switching the water to cold for a short time. This could be anywhere from 30 seconds to two minutes.

Are there any risks associated with cold water immersion?

In relation to swimming in extremely cold waters, there are risks associated with cold water immersion such as sudden heart attack, the loss of capacity to swim, hypothermia and drowning. What is known as the “cold shock” response is the initial cardio-respiratory response evoked by the sudden cooling of the skin. This places a strain on the heart, and the sudden loss of control over breathing leading to gasping means that the likelihood of breathing in water, even the small volume of water necessary to drown, is significantly increased. [9]

Be sure to get warm Immediately after you have practiced cold water immersion therapy – dry off well, put on some warm, drink something warm and sit somewhere warm. Avoid taking a hot shower as the sudden change in blood flow could cause you to pass out.

If you are planning on taking an ice bath or a cold dip in open water, ensure you have someone with you to monitor your condition.

Cold water immersion therapy may be worth a try

Cold water immersion isn’t just for athletes. By incorporating a cold shower into your daily routine or taking a dip in the ocean or your pool in winter, you may reap some of the benefits of this invigorating practice. A few minutes may be all you need. I have swam all year round in the ocean for many years and feel the benefits from cold water therapy, also regularly take cold showers to keep up the practice. Long term practice helps produce more brown fat in the body that is associated with many health benefits. I encourage you to give it a try.

Cold Water Immersion – Take the plunge?