Are cold showers as powerful as they seem?
Cold showers reading these words makes most people very uncomfortable. Let’s be honest, not many people enjoy feeling cold. However, in my search for optimal productivity, I am willing to try out even the strangest and most uncomfortable tricks and tools. Because as Bryan Mcgill puts it:
“Whatever makes you uncomfortable is your biggest opportunity for growth”.Bryan Mcgill
Cold showers are, in different ways, mentioned throughout the history of humankind. Hippocrates prescribed cold baths and in ancient Roman times, there were rituals with rooms of hot temperatures with a cold pool to end in. Nowadays, a lot of Olympic athletes take cold baths after training to recover quickly. It kind of seems like this cold shower thing should be a big deal. After reading some more very optimistic reviews of cold showers and The Wim Hof method, I started doing some research. Before believing any of the claims I wanted to see if there was any scientific research behind it.
Stronger immune system
The first study I stumbled upon was by Geert A. Buijze and his colleagues. They asked 3000 Dutch volunteers to end their morning shower with 30, 60, or 90 seconds of cold showering. In the study, they aimed to see the effect of cold showers on general health. They measured this through work attendance and how often the volunteers felt ill. They reported that both groups had the same amount of “ill days”. However, the ones taking cold showers had symptoms that felt less severe and reported higher energy levels. Due to this they were able to push through and did not have to call in sick to their work.
The research reports that the cold temperatures activate the brown (good) fat affecting our thermoregulation. Besides this, the cold may lead to an increase in energy. It also triggers our fight-or-flight response causing multiple hormones to increase after which a relaxation response follows.
The duration of the cold showers did not seem to have a big impact on the results that were detected. Which is a positive for me since the water does not have to be cold the entire shower.
With respect to productivity, this study noted that both groups reported the same levels whilst at work. However, since the intervention group (“cold shower group”) was absent less often they were more productive over the entire study period.
In the discussion of the research, they describe that 91% of people in the intervention group reported the will to continue the cold shower routine, of this group 64% actually did. Since it is not the most pleasant thing to do the participants must have gotten something out of it, right?
Cold showers impact your mood
According to this study, cold exposure activates the nervous system and can increase beta-endorphin and noradrenaline in the blood level up to 4-fold. Beta-endorphin is responsible for producing a sense of well-being and suppressing pain (through opioid receptors). The increased beta-endorphins therefore could have a positive effect on our mood as well as our pain tolerance. The increased synaptic release of noradrenaline through cold exposure is also very interesting. Because most antidepressant drugs are designed to increase the concentration of noradrenaline in the brain synapses. With increased beta-endorphins and the increased release of noradrenaline, the cold showers could positively affect our mood.
I also found a hypothesis: the lack of thermal stress to our bodies is a contributing factor to depression. Most of the evolution’s transient changes in body temperature have been present, nowadays through the invention of clothes, heated shelter, and an indoor lifestyle these changes in body temperature are far less occurring. Humans are homeotherms, meaning that their body maintains a constant temperature around 36.6 °C. However, the lack of use of the regulatory system in a relatively short period of time could have some negative effects on human health, including mental health. If this hypothesis turns out to be correct, exposure to cold via cold showers could be a good stimulant to the body with positive effects on overall health.
Cold showers and physical recovery
I don’t consider myself an athlete, however, I do try to exercise about 5 times a week. Doing this makes me no stranger to muscle aches. Therefore, it can’t hurt to look at how the professionals use cold showers to recover from exercise. For athletes, recovery is crucial due to the length and amount of training. Therefore, they have many different techniques to help them recover quickly. These techniques include different foods, active recovery, but also cold water immersion. An article described the following possible physiological benefits to cold water immersion:
- Intracellular–intravascular fluid shift
- Reduction of muscle edema as well as increased cardiac output helping with enhanced blood flow
- Nutrient distribution
- Waste transportation
This means that extra fluids are distributed to reduce fluid retention, nutrients get transported to the areas in the body that need it, and waste (like lactic acid) will get transported out of the body.
The cold water can also move fluid from extravascular space to the vascular component through hydrostatic pressure. This reduces the increased muscle volume which is caused by the exercise. This reduction can in turn reduce soft tissue inflammation. This can also be achieved by active recovery, however, doing it through cold water preserves some extra energy.
The article also speaks of the reduction of muscle soreness which can be achieved by taking contrast showers or baths. In combination with the increase in beta-endorphins, which could also have a positive effect on our pain tolerance, cold showers seem to be able to reduce muscle pain after training.
Multiple studies have found a connection between exposure to cold temperatures and the activation of brown fat. Brown fat (also known as brown adipose tissue) is a type of fat in humans that contributes to the transfer of energy into heat. These studies also found if you have activated more brown fat you are more likely to have a healthy amount of white fat (also known as white adipose tissue), resulting in a healthy BMI (Body Mass Index).
Besides activating brown fat, cold showers will also directly increase a person’s metabolic rate since the body is working harder to keep warm. However, this amount is not as high as the overall increase in a person’s metabolic rate through the activation of brown fat.
Taking cold showers can thus be effective for people who like to lose a few pounds. You can read more about this in these studies: 1 & 2.
How to take cold showers
According to this article “brief whole-body exposure to cold water (15–23 °C) appears to be safe, and was not shown to have any significant side-effects either short-term or long-term”. However, when showering cold in the winter (depending on where u live) the water might be colder than 15 °C. In the first Dutch study for example the water was around 10-12 °C. So, here are some pointers to safely benefit from cold showers:
- Start your cold shower by getting your wrist, arms, and legs wet. Doing this will give you some time to get used to the temperature.
- Listen to your body. Cold showers are pretty intense but you should not feel lightheaded or sick during them. If you do start to feel too uncomfortable you could slowly turn the water warmer. If you feel better after some time you could consider slowly going cold again. By doing this you have turned your shower into a contrast shower instead of a cold shower.
- Take cold showers consistently.
- Maybe don’t start taking these showers after 7 p.m. I have read some articles and experiences about people having a hard time sleeping when they do take a cold shower after 7 p.m. Maybe once you started taking cold showers consistently you could try it out and see what time works for you.
Please do know that cold showers should not function as a replacement for medical therapies or medicine without the consultation of a doctor. Also, people with a weaker immune system, high blood pressure, or heart conditions should be cautious with cold showers. The cold can rapidly change the body temperature and affect the heart rate which might be too much for your body. In case of any of these conditions consult a doctor before starting to take cold showers.
Something which I could find in scientific research but do find in the writing of other people’s experiences is heightened willpower. Of course, nobody likes feeling cold, maybe except Wim Hof. However, doing things you really don’t want to do is a great workout for your willpower. I normally challenge myself to do everything the little voice in my head tells me not to do. So in this light, the 30-day cold shower challenge seems right up my alley.
After reading all the benefits and health statements of cold showers backed up by different studies I think it is definitely worth a try. It is a case in which, for me, the benefits certainly outweigh the risks. So I will set a goal for myself: to take a cold shower every day for 30 days in a row. This will truly let me face my coldest fears. Once I complete 30 days in a row I will share my experience in a blog post.