Cold Water Immersion (CWI) therapy is gaining in popularity with athletes and wellness advocates alike. Supporters from cannabis advocates to wellness influencers tout its psychological and physiological benefits.
Many elite athletes—from four-time Formula 1 world champion Max Verstappen to English footballers Alessia Russo and Lucy Bronze—vouch for recovery practices, such as ice baths. Scientists cautioned that the evidence supporting these claims remains scant and largely hypothetical. Professor Mike Tipton, one of the world’s foremost hypothermia experts, calls the evidence for CWI “big stuff.” Especially in contrast to its alleged benefits, he explains that the dangers of CWI are unmatched.
CWI is perhaps the most popular recovery method employed following high-intensity exercise. Like the members of the Bluetits Chill Swimmers in the UK, who have weekly ice bath swims together. As a result, cold water can cause you to experience a sudden and perilous response called “cold water shock,” cautions Professor Tipton. This risk is compounded when temperatures drop below 15 degrees Celsius. The health risks of this reaction can be significant, especially for those not used to the physiological effects of extreme cold.
Limited Evidence on Benefits
University of South Australia researchers undertook the recent study. The researchers wanted to see if post-exercise recovery could be improved by using cold water immersion (CWI) following an intense game of soccer. The research provided program, health, and wellness managers empirical evidence that participants felt less stressed after going through CWI. This effect was only seen 12 hours post-immersion session. There were no statistically meaningful changes in mood or quality of life.
Professor Tipton pointed out that while some individuals report positive experiences with CWI, these claims often lack rigorous scientific backing. He remarked on the wealth of anecdotal evidence present on social media platforms, stating, “Most of the information that’s out there on social media is word of mouth, and anecdotal evidence.” He mentioned that several positive claims related to CWI lack evidence-based rigorous research to prove them.
“Nobody has really done properly controlled studies to isolate the active ingredient in the experience of going for a dip… is [the benefit] coming from green therapy, blue therapy, exercise, meeting people, having cake and coffee, or all and any of those?” – Mike Tipton
The policy toolkit to support federal CWI efforts is further complicated by this confusing patchwork of research. One of the studies referenced by Professor Tipton found an impressive 29% decrease in sickness absence among CWI participants who used CWI. As an example, The University of South Australia was only able to locate 11 “quality” studies on CWI. This monumental discovery underscores an urgent need for research on its efficacy and safety.
The Habituation Theory
One theory suggested by Professor Tipton is that the repeated exposure to cold water can teach a person to acclimatize themselves to stressful situations. This concept suggests that individuals who consistently engage in CWI might develop a greater resilience to various stressors over time. He continued that the theory then postulates that cold water immersion provides the greatest benefits. It literally prepares your body to deal with the strain from a physiological standpoint. You just get less responsive to the stressor, and perhaps that generalizes to other stressors.
A new study serves as further evidence for this hypothesis. Participants who underwent cold water immersion performed better than those immersed in warm water during subsequent altitude training sessions. This confirmation jives with what we’ve been hearing anecdotally from people practicing CWI.
“I’ve had some of the Bluetits ladies come up to me in tears telling me how this has changed their life, how they used to have mental health problems and don’t have them anymore,” – Mike Tipton
While some participants report transformative experiences related to mental health improvement, Professor Tipton cautioned against accepting these claims at face value due to their anecdotal nature. He emphasized the importance of grounding claims in scientific evidence, stating, “The problem with that is that the evidence is anecdotal. Anecdotal evidence is still evidence, but it’s the weakest form.”
Safety Considerations
While Professor Tipton recognizes that most people who engage with CWI practices have no negative intentions, safety must be prioritized. He stated, “It’s fine if that’s what they want to do: I’m definitely not the fun police … but I want to make sure that I give them information to make sure they can do it as safely as possible.”
The dangers of cold water immersion are not to be underestimated. Cold water shock triggers a number of physiologic responses, some of which can be lethal for certain people. Thus, knowing how to participate in CWI safely is of utmost importance to those who wish to seek its many potential benefits.
Tara Cain, a researcher who has participated in CWI studies, shared her worries on the lack of evidence that exists to apply broadly. She remarked, “I think the overarching message from this study is that there’s such limited evidence out there that needs to be explored more to apply to the general population.”
