Cold showers. Being on an army base comes to mind, or possibly prison. Either way, cold showers tends to conjure up a punitive element. People who take cold showers willingly when they actually have access to hot water? Well, they must be masochists, or else oddly inured to ordinary human sensation. Or a bit mad.
But science is proving something that humans (and probably lots of animals) too have known since time immemorial; that cold water is an amazing tonic for the body and mind, and yes, you can get yourself to the point where not only do you no longer mind the cold, you actually look forward to it.
Understanding how to recruit the Vagus Nerve is a significant step towards calming the sympathetic fight and flight response and engaging the tend and befriend response of the parasympathetic pathway. The science on the subject is growing fast, and we now have several to reference that demonstrate cold exposure to improve ‘vagal tone’, a key metric of a healthy and responsive nervous system and is adaptive and resilient to stressors.
Vagal tone is measured through the physiological phenomenon of heart-rate variability (HRV). HRV refers to the differences in length of time between our heart beats. A healthy heart does not keep perfect military band rhythm. Surprising as it may seem, it is actually healthier to have slight differences in the interval lengths of your heartbeat. The interval between beats becomes shorter when we breathe in and longer when we breathe out, for example, a feature called respiratory sinus arrhythmia (RSA). HRV is largely influenced by Vagus Nerve activity; and cold exposure is one bottom up (body-first) approach to engaging the Vagus Nerve. This is why cold showers in moderation can be good for the heart among many other things.
Various research has shown that regular cold water exposure:
- improves mood, even combating serious depression
- increases alertness and concentration
- boosts the immune response
- reduces inflammation
- improves insulin sensitivity thus reducing the risk of diabetes
- improves cardiovascular health
- helps to combat stress
- helps to burn fat
- increases circulation
- improves the condition of the skin
- promotes healing of muscle injuries
But there are several myths about cold water exposure. As someone who took A LOT of convincing to even try cold water exposure, I know how these myths stood in the way of taking the plunge and reaping the many benefits that this simple, cheap and effective intervention has to offer.
Myth 1: The whole shower must be cold.
I never take a cold shower. But I regularly take cold ‘rinses’. This means that I take a hot shower first to wash and scrub and then I turn the dial to cold and use the nozzle for very targeted exposure on certain parts of my body. This is very different and far more tolerable than stepping directly into cold water.
Myth 2: You need to be shivering cold
No, you don’t. I never go so far as to shiver because it is not necessary for the water to be freezing cold. Science has shown that you don’t need to go under 68 F/20 C to reap many of the benefits discussed here. This is equivalent to cold pool water. You can start with a warm rinse, and then each day adjust to go just a little bit colder. I never measure the temperature of my cold rinses, I just turn the dial to the cold. Strangely, I find it easier to take cold showers in the winter rather than the summer. Maybe this is because I have the heat on in the bathroom.
Myth 3: You need stay under for several minutes.
Even two or three minutes is enough. One study in the journal Medical Hypotheses found that participants who took regular two-to-three minute cold showers of 68 degrees over a two-week period found that their mood measurably improved.
Myth 4: You need to stand under the water
I was very resistant to taking cold showers, even as ‘rinses’ in the beginning. I had a particular aversion to the idea of putting my head under the cold water. I was happy to learn that this is actually not necessary, and in fact, targeted cold-water exposure with a shower nozzle can be even more effective than immersing yourself completely.
The ‘targeting’ part turns out to be key. Cold water exposure increases blood flow to deep tissue and so can help to repair damaged muscles because your blood contains nutrients that heal. Focus the spray on the area that’s aching or giving you trouble. This technique helped me enormously while I was healing from a sacroiliac joint problem that was giving me pain in the hips and lower back.
Research carried out by the Institute for Health and Behaviour at the University of Luxembourg found that cold exposure specifically targeting the sides of the neck and the cheeks of the face was effective in stimulating Vagus Nerve activity as measure by heart rate variability.
Myth 5: You will feel colder when you get out
Actually, you will feel warmer. Try it for yourself and see. Take a normal shower, and notice your body temperature before you step into the shower stall, and again when you get out. The next day, add a cold rinse to your routine and again pay attention to your body temperature. You will notice that you feel warmer after the shower than when you went it. And this increased warmth can stay with you for hours. The reason you feel warmer after a cold shower is because cold increases our core temperature through increased circulation. Increased circulation is one of the top reasons experts recommend cold showers. As cold water hits your body, it constricts circulation on the skin surface. This causes blood in your deeper tissues to circulate at faster rates to maintain ideal body temperature.
Below are links to several studies on more benefits of cold exposure:
Cold water swimming has been shown to combat major depressive disorder
Improved insulin sensitivity
Cold exposure reduces insulin resistance, and so reduces the risk of diabetes
A study found that participants who swam in ice-cold water on the regular showed an increased tolerance to stress—all thanks to their bodies adapting to the repeat exposure.
Improving the condition of the skin
Hot water actually strips natural oils from the skin and dries it out. Cold water helps to condition the skin. It constricts blood vessels which tightens pores, protecting against pollution and helping to maintain the skin’s firmness and hydration.
Cold showers jumpstart your metabolism and may help with weight loss by increasing the activity of brown fat, a special type of fat that produces heat and burns calories when the body gets cold.
Boosting the immune system
There are many studies on the connection between cold exposure and an enhanced immune system. Taking a cold shower increases the number of white blood cells in your body, the cells that protect you against diseases.
A fascinating clinical trial in the Netherlands found that cold showers led to a 29% reduction in people calling off sick from work.
Another study connected cold showers to improved cancer survival.
So, in short there are many reasons to be bold with cold. And you will feel like a superhero, I promise you!