Standing half-naked on a muddy patch of riverbank, fighting both feelings of apprehension and an uncontrollable shiver, whilst staring out at the mirky façade of what has become my regular swimming pool, in that moment at least, doesn’t feel like the key to anything, except some imminent and rather powerful discomfort. Five intense minutes later however, with numbed hands and redded skin, I emerge with a re-doubled allegiance to the church of cold-water immersion.
Perhaps a surprising trend for a culture increasingly intend upon the pursuit of quick fixes and instant gratification, therapy through exposure to cold water occupies a spot in the wellness, self-improvement zeitgeist which is becoming hard to ignore. Being touted, inevitably, by some Viking-like master of the cold who advocates for the practice with a nigh on religious zeal, and promising benefits ranging from all the way from physical performance, to psychological proficiency, to prophylactic protection! Indeed, this was my experience coming across the, now high profile celebrity, Wim Hof – an eccentric Dutchman who developed a his own method of breathing combined with cold exposure to improve his own mental and physical health. Wim is unashamedly his own loudest hype-man when it comes to the success of this method, boasting that the cold has the power to heighten your senses, improve your mood and even bolster your immune system. These are all bold claims, and considering the level of popularity Wim and others have garnered on their basis, it is only right that we hold some icy feet to the fire and investigate them.
For me, the question not whether there are any benefits to cold water immersion, as surely an activity which is active, outdoors, and requires considerable power of will to accomplish cannot be unhealthy. Indeed, the testimonies of enthusiasts, and the fact that people are doing it at all, speaks to some tangible positive which cannot be disputed by any particular scientific inquiry. The question instead becomes what exactly draws us to the cold, and how many of the benefits we feel can be put down to scientifically verifiable phenomena, alternatively, to what degree might they be attributable to a powerful placebo.
Historical Precedent:
Unfortunately, instances of our ancestors venturing into the cold for its own sake are rather few and far between. Although there exist references to the therapeutic effects of cold in certain ancient texts, such as the 3,500BC medical treatise known as the Edwin Smith Papyrus and the writings of the ancient Greek Hippocrates, these recommend a more localised application of cold, in order to treat particular conditions and aid in surgeries. When researching this topic, many instances of so called “cold therapy” were of this kind; cold was a tool often utilised for its numbing properties and applied to specific bodily regions, rather than the kind of full body immersion that we’re interested in.
That said, the Hippocrates and other ancient Greeks arguably dipped more than a toe into the cold. Often cited in the history of cold therapy is the Hippocratic theory of “humours”. This explained health and disease with reference to a balance of liquid within the body, and prescribed therapies designed to restore this balance which involved more general immersion in cold – for instance, to bring down a fever. Indeed, this idea of the cold as an equalising force seems to have been compelling to the ancient world, a prime example being the well-known historical practice of bathing in both Greek and Roman culture.
More than a simple hygiene ritual, bathing was a serious business, for the Romans especially, who dedicated extravagant works of architecture and many hours at a time spent soaking in vast public pools. Interestingly, this practice involved both conventional heated baths and a colder plunge pool known as the frigidarium, which would serve as a contrast to balance out an otherwise sweaty, oily, and steamy affair. Still more interestingly, this pool was artificially cooled by the use of snow, not simply left at room temperature. Although it is unclear exactly how cold these frigidarium’s would get, and therefore whether they would impress the modern-day ice man who recommends chiselling your way into a frozen lake mid-water to create your plunge pool, they do imply a certain respect for the therapeutic effects of the cold which was held, not merely by a few enthusiasts, but rather Roman culture at large. This is encouraging, during at least one point in human history immersion in cold water was something ordinary people did and was widely accepted as part of a healthy lifestyle.
After the Romans and their frigidarium’s fade into history we are hard pressed for another example of cold immersion in the proceeding centuries, and especially one which reaches a comparable level of cultural uptake. Notable exceptions can be found in the scientific and medical research conducted in the 19th and 20th centuries, wherein the cold was studied for its effects on the nervous system and blood pressure. Such inquiries were, however, not aimed at discovering the therapeutic effects cold immersion, but rather what it can teach us about the way our bodies function.
This first real application of the cold as therapy in modern times was as a method of post-exercise recovery, which has its origins in the 1960s and the work of D H Clark. Apparently ahead of his time, Clark’s work, and the use of cold-water immersion for athletes, did not gain mainstream attention until the 90s, but since then a plethora of studies and analyses on the topic have generated the generally accepted consensus that, in the field of physical performance, the cold is a force for good.
Modern Science:
This about brings us to the modern understanding of cold-water therapy, as being an effective tool for athletes to maximise the efficiency of muscle recovery. The science of this phenomena is explained through the effect of the cold in slowing a person’s metabolic rate, thereby reducing the rate of tissue breakdown, and easing those post-workout pains. Now, although this discovery may validate the notion that a cold plunge has more to it than mere superficial shock and awe, it doesn’t seem particularly relevant to the trend we are investigating. For the non-Olympians among us – all of us then – and for the gurus extoling the benefits of regular icy immersions, the goal is not to eke out an extra sliver of athletic performance, but rather to aid in the living of a more typical lifestyle. Indeed, the practice endorsed by the likes of Wim Hof, as depicted in the BBC show “Freeze the Fear”, promises benefits for the average joe, with unambiguous emphasis on the phycological as opposed to the physical. The question remains therefore, are these sorts of benefits real? Or were the Romans simply all avid sportsmen who had happened upon the cold as a way to gain a competitive edge? Unlikely, but how then can we explain either this historical instance of widespread participation in cold water therapy, or the trend we are currently living through?
The explanation I am subconsciously trying to avoid, whilst searching for some irrefutable validation from dense and occasionally incomprehensible columns of academic text, is that these elusive benefits are primary the result of a potent yet mere placebo. Perhaps the ritual of getting out into nature, mentally psyching oneself up before voluntarily wading out into discomfort, and the brief yet powerful rush of adrenaline and endorphins is enough to convince us that something good must be going on. Perhaps this in-the-moment high permeates our psyche in an unremarkable way: we look forward to getting into the cold, and, after the fact, we feel good about having done so. Now, let me be clear, this possibility – if slightly deflating for the die-hard evangelist – does not discredit the practice by any means. In fact, we shouldn’t really use the word mere to describe placebo, because there is nothing insignificant about a phenomena frequently used to great effect in treating ailments such as pain, stress, nausea etc. As Professor Ted Kaptchukat over at Harvard Health says, “The placebo effect is more than positive thinking — believing a treatment or procedure will work. It’s about creating a stronger connection between the brain and body and how they work together”. Although placebo will not cure a disease or condition, it can have a real impact on the mind’s relationship to the body, thereby improving wellbeing in a very tangible sense. If people are reporting an increase in wellbeing by participating in any practice, something positive must be happening somewhere, even if we cannot find any particular biological reaction which links the practice to the wellbeing in a necessary, scientific sense. As the hedonist mantra goes: if it feels good, do it.
That said, however, we need not be hasty in crediting all these good feelings to the power of placebo. Having browsed the most recent academic literature on cold water immersion (or CWI as the boffins refer to it), there seems a significant interest in potential health benefits beyond those established in the realm of elite athletics. One particularly interesting study compiled multiple investigations into CWI, thereby generating a nuanced discussion which took the effect of CWI on a broad range of physiological markers into account to establish possible health benefits and risks. This discussion, whilst ultimately emphasising the need for ongoing research and debate, presented encouraging findings which give us some hope that the benefits that are not all in our heads.
Firstly, one of the more conclusive findings was the effect of CWI in the reduction of “body adipose tissue”, otherwise known as body fat. It turns out that the body will break down or transform this type of tissue in order to release heat when it needs to warm up fast, as a result this study suggests that regular CWI could have positive impact on cardiovascular health and reduce the risk of conditions such as diabetes. Additionally, and perhaps still more encouraging, was the possibility of CWI to reduce stress and inflammation throughout the body. Indeed, the link between these afflictions and health/disease is one of growing scientific interest, with low levels of inflammation being found to predict healthy and successful aging while high levels are associated with immune system disorders. Increased levels of certain substances (with unnecessarily long and technical names), which are known to have anti-inflammatory effects, were found to be in significantly higher concentration both immediately following CWI and after a six-week period. Now, there are caveats here before we get too excited; these studies were not perfect, and there are questions around whether this increase was caused specifically by CWI, or whether they are partially or fully down to other factors such as lifestyle. We might expect a regular cold-water swimmer to live a healthier, more active lifestyle than your average warm-showering civilian. So more research is needed, but so far, there is nothing in the cold hard facts to make us shiver.
Perhaps the most compelling motivation for some, and the most compelling claim by the likes of Wim Hof, is that the cold can have powerful psychological effects – boosting mood and even treating depression and anxiety. Unsurprisingly, testimony from regular plungers will give you this impression emphatically; the activity itself is described (according to one questionnaire) as resoundingly exhilarating and joyful, with physical symptoms of stress relieved and mood elevated. Whether these results can be put down to some particular effect of the cold on our neurology, and how much is down to (no mere, mind you) placebo, seems a tricky question we do not presently have the means to answer. The study mentioned earlier does, however, hypothesise that the stimulation of “cold receptors” in the skin during CWI could have an “anti-depressive” effect as a result of the “strong afferent input to the brain”. I must admit I lack the necessary technical knowledge here to give an optimal translation, but after some more academic skimming, it seems what is being suggested is that the intensity of the sensory input from the cold water could be enough to promote some mood boosting, anti-depressive effect, which could explain feeling energised and joyful both during and post swim. This makes pretty good sense to me anyhow, and, although this is only one proposal requiring much testing, debating and general beard scratching before reaching any kind of scientific consensus, I might just take it with me on my next CWI, because, as the placebo effect shows, if you think something makes you feel good, then it probably does.
In this discussion I have tried to present the most convincing, or at least promising, pieces of evidence which could support cold water swimming as a serious therapeutic practice for the body and/or the mind. As far as key takeaways go, it is clear that more research in the academic field is needed to for CWI to be uncontroversially accepted for its positive effects, and, consequently, we shouldn’t hold our breath for its entry into the coveted pantheon of clinically approved practices. However, along the way we have uncovered multiple cases of wherein both history and science appear to lend real credence to the, let’s say hypothesis, that the cold is good for you. Indeed, at the end of the day, we don’t need some peer reviewed study to validate what we can empirically see for ourselves is positive, although perhaps those claiming that all the blind and the lame need to be cured is the odd cold shower, and plunge in the river, should ease up on the rhetoric slightly. That said, I would recommend we keep on plunging, whether it’s for some specific chemical reaction triggered in the brain or body, a psychological challenge to test the mind and build discipline, or because it just plain feels good.