How to practice ice baths to manage stress
Summary
Despite the conventional wisdom that stress is unhealthy, decades of scientific research shows that beliefs about stress are more important than stressful experiences.
Moderate amount of stress can be healthy and build resilience.
Cold water immersion is good stress practice.
Practicing stress management skills may extend lifespan by improving vascular health when under stress.
Is stress bad?
The internet is deluged with articles and advice on stress reduction, all predicated on the idea that reducing stress will improve health and happiness. In fact, the idea that stress might be good for you is so foreign, so strange, so heretical, that when you search Google for "How can I increase my stress?" the first page of results provides articles intended to help you decrease stress instead.
Stress increase is the only Google search that yields the opposite of what you search
for. For example, if you search Google for "How do I gain weight?" you get results on
weight gain. If you search for, "How do I get dumber?" you get articles about how
stupid you already are, and a listicle that describes '17 Things That Make You Dumber' that mentions reality TV, sugar, chewing gum, and stress.
Evidently stress is in the special category of conditions that no one wants more of --
except perhaps for the late Hans Selye, PhD (1907-1982), who has been called “the founder of modern stress theory” because he practically invented the concept (Tan et al. 2018).
"Contrary to public opinion, we must not -- and indeed cannot -- avoid stress, but we can meet it efficiently and enjoy it by learning more about its mechanism and adjusting our philosophy of life accordingly." - Hans Selye (1973).
For Selye, our response to stress is important than the stress itself. He wrote that
“disease can be produced indirectly by our own inappropriate or excessive adaptive
reactions” to perceptions of stress. For example, Selye says that our attitude when confronted by stress is critical for avoiding self-imposed damage from our own reactions to stress. He points out that a fight response will "discharge adrenalin-type hormones that increase blood pressure and pulse rate, while your whole nervous system will be come alarmed and tense in anticipation of combat."
Given the toll placed upon the body by over-reaction to stress, false alarms could be disastrous, rather than protective. For Selye, our stress response is a choice.
Cold stress science
When psychologists study stress, many of them use a protocol called the Socially Evaluated Cold Pressor Test (SECPT, Schwabe et al 2018). The test requires subjects to immerse one hand in freezing cold water for 3 minutes, while other people are observing.
Although it doesn't sound very stressful, the protocol elicits a strong response from the sympathetic nervous system (Schwabe et al. 2008). When the hand goes into the freezing cold water. thermoreceptors in the skin signal the hypothalamus that there is an impending danger. Without the brain having to give it an conscious thought, the hypothalamus initiates a cascade of emergency responses including:
smooth muscles tissues surrounding the blood vessels contract, squeezing off blood flow to the exposed areas to defend core body temperature (i.e., vasoconstriction),
the liver releases glycogen to spike blood sugar so skeletal muscles have the fast energy they will need for fight-or-flight,
brown fat activates, burning glucose and triglycerides from the bloodstream for cold thermogenesis,
heart rate and blood pressure jump, in anticipation of the cardiovascular demands of danger, and
a surge of noradrenaline, dopamine, and other neurotransmitters flood the brain.
It is in that moment when you can make the choice to either panic or relax.
Ice bath breathing
Patrick Porter, PhD is an accomplished psychologist and inventor of the Brain Tap headset that uses light and sound to stimulate meditative brain activity. Porter hadn't experienced an ice bath since he was Captain of his High School football team, when he used to occassionaly soak his legs after a tough practice. And he'd never done whole-body cold water immersion before.
With Jerame Mudick guiding him, in the video below you can see Porter's gasp reflex, his panic response, and when he makes the choice to calm his body by structuring his breathing.
The famous Austrian psychologist Viktor Frankl popularized the realization that we are not slaves to our autonomic nervous system. That is, we can choose our response.
“Between stimulus and response there is a space. In that space is our power to choose our response. In our response lies our growth and our freedom.” - Viktor Frankl (1905-1997)
Breathing is the key that unlocks control.
Breath exists in that space between the autonomic and the voluntary -- what science journalist Scott Carney calls The Wedge (Carney 2020). No one has to think about breathing -- it happens automatically. But almost everyone can take control of their breathing for at least a few minutes when they choose to.
Cold water stimulation can cause an involuntary gasp -- as if your body was preparing for an extended underwater immersion and it wants to fill your lungs with as much air as possible just in case you dive in. Without conscious control, the gasp reflex can turn into an uncontrolled hyperventilation until the cold stimulus (i.e., the danger) is removed.
However, when you practice structured breathing during cold stimulation, a strange thing happens. Your heart rate slows back down and despite an increase in overall activity, your brainwaves shift towards a more calm, meditative state.
Stress training
Few people can last a full five minutes of the cold pressor test. When every instinct in your body is telling you "Get your hand out of there!" it's hard to stay calm. However, studies show that repeating the cold exposure results in less drastic changes in physiological biomarkers of stress.
That is, subjects in cold pressor studies learn to improve management of their stress response.
For example, when researchers in Germany administered the SECPT to an experimental group of men and women over three consecutive days, they found that physiological markers of stress on the 3rd day were lower than those on the first two. Blood pressure and perceived stress levels came way down, and heart rate dropped so far that by Day 3 it was lower in the cold-stimulated group than in the control group (Minkley et al. 2014).
A more recent experiment that compressed all three cold exposures into a single day showed similar improvements in heart rate (Larra et al. 2023). In other words, what feels like automatic, physiological stress responses can actually be retrained by practicing new outcomes with repeated exposure.
This findings are consistent with a 2010 study conducted at the State University of New York at Buffalo in which researchers sorted out participants according to the number of adverse events (such as assault, death of a parent, or natural disaster) they'd experienced. When they administered the cold pressor test, they discovered that people with a moderate exposure to adverse events tolerated the cold stress better than people with none (Seery et al. 2010). They theorized that experience with one type of adversity could build skills that make a person more resilient to other types.
"Experiencing a moderate number of serious negative life events may contribute to developing a propensity for managing well in the face of stressors. This propensity seems to generalize to new domains and does not depend on other potential coping resources and liabilities. These results do not suggest that adversity lacks negative consequences or that it should be encouraged. Instead, however, adversity exposure may have an upside: future resilience." - Seery et al. (2010).
Make stress management a habit
The world's foremost expert on the SECPT is Lars Schwabe, Professor of Cognitive Psychology at Ruhr University in Bochum, Germany. To discover more about stress response, he designed an experiment comparing two distinct processes that are known to influence behavior:
incentives, and
habits.
What he discovered is that habits are much better predictors of behavior under stress than incentives (Schwabe & Wolf 2009).
Given what we've learned about human cognition and decision-making from Daniel Kahneman's Thinking Fast and Slow (2011), we know that goal-directed behavior guided by incentives requires a much greater cognitive load. That is, incentive-driven thinking is slow. But habits require so little thinking that habitual behavior happens fast.
Under stress, resources for slow thinking are scarce. Our cognitive processes can be overwhelmed by our body's physiological response to stress, interrupting the slow thinking necessary for incentive-driven behavior. That's when we must rely on our habits.
What this suggests is that the only way to improve our stress response, and maybe our performance under pressure, is to practice experiencing stress so that we can form better habits.
Because cold exposure is proven to induce stress, the ice bath is the perfect way to practice improved stress response habits. That way, when we're in an argument with our spouse, or we're getting chewed out by the Boss, or we're anxious about bills, we can remind ourselves of the way we breathe and calm our bodies in the ice bath, and transfer those skills to manage stress in other situations.
Stress for long life
Training yourself to overcome the stress response to cold exposure may extend your life. In her 2013 TED talk 'How to make stress your friend', Stanford Psychologist Kelly McGonigal. PhD reports that it is not stress that kills you.
It is the story you tell yourself about that stress.
In her book, The Upside of Stress (McGonigal 2012) she writes that merely believing that stress is harmful could be the 15th greatest cause of premature death in the United States. She cites a 2012 study that showed only the people who reported both experiencing a lot of stress and the belief that their stress was adversely impacting their health were at an increased risk of mortality (Keller et al. 2012).
To retrain her subjects to improve their stress response, McGonigal administers a socially evaluated stress test in her laboratory. That is, she uses the social evaluation portion of the SECPT, but not the cold pressor portion. She concludes that subjects who were told that their stress responses are helpful experience more relaxed blood vessels, despite elevated heart rate. The relaxed blood vessels are associated with better vascular health, and reduced risk of clotting and the heart attacks, stroke, or deep vein thrombosis that can result from clots.
What's really interesting is that McGonigal doesn't teach her subjects how to change their own beliefs about stress. For the purposes of her study, she simply tells her subjects that their stress is healthy. Evidently, hearing it from her is good enough for them.
Protocols for ice bath stress
As far as I know, McGonigal herself has never attempted an ice bath, and it may be because she holds some pretty strong beliefs about cold. In her description of the cold pressor test, she wrote "If you were to immerse your whole body in water this cold (34F), it would kill you in less than a minute."
That might be exactly what your hypothalamus is programmed by evolutionary biology to believe, given that over reaction to stress might have helped protect our ancestors from real dangers tens of thousands of years ago. However, we know from the experience of hundreds of thousands of people doing ice baths around the world, that McGonigal's mortal fears of cold aren't true.
When you find yourself experiencing the natural, autonomic panic response in your ice bath, and it seems like every cell in your body is screaming at you "We're going to die!" you can use the mantra "This is what cold feels like," while you structure your breathing.
Your brain and your body will calm down. You will relax.
And that may extend your life.
References
Carney SG. 2020. The Wedge: Evolution, Consciousness, Stress and the Key to Human Resilience: Foxtopus Ink.
Kahneman D. Thinking, Fast and Slow. Macmillan; 2011
Keller A, Litzelman K, Wisk LE, Maddox T, Cheng ER, Creswell PD, Witt WP. Does the perception that stress affects health matter? The association with health and mortality. Health psychology. 2012 Sep;31(5):677.
Larra MF, Capellino S, Schwendich E, von Haugwitz L, Reinders J, Wascher E. Immediate and delayed salivary cytokine responses during repeated exposures to Cold Pressor stress. Neuroimmunomodulation. 2023 Jan 4;30(1):81-92.
McGonigal K. The upside of stress: Why stress is good for you, and how to get good at it. Penguin; 2016.
Minkley N, Schröder TP, Wolf OT, Kirchner WH. The socially evaluated cold-pressor test (SECPT) for groups: Effects of repeated administration of a combined physiological and psychological stressor. Psychoneuroendocrinology. 2014 Jul 1;45:119-27.
Schwabe L, Haddad L, Schachinger H. HPA axis activation by a socially evaluated cold-pressor test. Psychoneuroendocrinology. 2008 Jul 1;33(6):890-5.
Schwabe L, Schächinger H. Ten years of research with the Socially Evaluated Cold Pressor Test: Data from the past and guidelines for the future. Psychoneuroendocrinology. 2018 Jun 1;92:155-61.
Schwabe L, Wolf OT. Stress prompts habit behavior in humans. Journal of Neuroscience. 2009 Jun 3;29(22):7191-8.
Seery MD, Leo RJ, Lupien SP, Kondrak CL, Almonte JL. An upside to adversity? Moderate cumulative lifetime adversity is associated with resilient responses in the face of controlled stressors. Psychological science. 2013 Jul;24(7):1181-9.
Selye H. The Evolution of the Stress Concept: The originator of the concept traces its development from the discovery in 1936 of the alarm reaction to modern therapeutic applications of syntoxic and catatoxic hormones. American Scientist. 1973 Nov;61(6):692-9.
Tan SY, Yip A. Hans Selye (1907–1982): Founder of the stress theory. Singapore medical journal. 2018 Apr;59(4):170.
About the Author
Thomas P Seager, PhD is an Associate Professor in the School of Sustainable Engineering at Arizona State University. Seager co-founded the Morozko Forge ice bath company and is an expert in the use of ice baths for building metabolic and psychological resilience. Subscribe to https://seagertp.substack.com/ for more information from Seager on taking charge of your own physical & mental health.