The Psychology of Cold Plunging

What I learned from cold plunging every day for a month

James Garrett

“This is a really good idea…This is such a good idea. I can’t believe what a good idea this is…This is my idea. I was the one who had this idea…Oh, it’s such a good idea!…I…I…Oh…oh…ooo…ooooo….ooooooo…ooooooooo…oooooooooooooo.”

And so it began. My month-long journey to embrace the discomfort of 33℉ water and learn what it had to teach me.

This is not my jam. I hate cold water. Growing up, my family would often tease me for being the last to get in, to which I’d retort: they clearly don’t know how sensitive my skin is.

So why did I decide to do the very thing I hate? What good could possibly come from this uniquely modern form of torture?

Well, it got into my head. It was the biology and psychology of it that intrigued me the most. On the biology side, there is a laundry list of health benefits from cold water exposure. On the psychology side — the head game of cold exposure was just too juicy to pass up.

Brains instinctually avoid pain, so how do you get the brain to do something it doesn’t like? Could I actually get myself to do it daily? And if I did, would the experience get easier over time? Was it really possible to train my brain to embrace discomfort? Maybe even like it? I had to know.

While this whole thing might seem like a bizarre offering to the gods of gratuitous suffering, as you read on, you may discover, as I have, that cold plunging packs a surprising punch — it’s far better than I ever expected.

But first, the pain.

In the Beginning...

It wasn’t the most graceful start. I created a make-shift bathtub on my back porch (out of a 45-gallon Husky bin from Home Depot) and on my first day, after cracking the ice on the surface, I took the plunge into the coldest water I’ve ever been in (33℉).

I got in quickly and it sent my nervous system spinning. I thought I would scream, but the opposite actually happened — the cold shock was so intense, it felt like my vocal cords were paralyzed. All I could do was attempt to slow down my breathing. (You can see it here.) It only lasted for 33 miserable seconds, and while it may not have been the most graceful start…it was, indeed, a start.

The Headgame of Procrastination

By Days 2 and 3, my brain was convinced that this was definitely a bad idea. I would find myself picking up the house, looking at email, washing the dishes — pretty much anything to procrastinate doing the plunge. Some mornings, I would avoid it for hours. This period of avoidance had me worried that the whole experiment might unravel.

In fact, after the first 3 plunges, I felt like I had to take the weekend off (lucky for me, the tub froze solid after a wicked winter storm).

"Could it be that there is a physiological conflict in the system during cold-water immersion?"

John Doe

That weekend, I realized that if I was going to keep doing this, I had to figure out how to do it better and understand why I felt so panicked on days 1–3. I was also committed to listening to my body and my body was telling me I needed some space to decompress or I might start layering tiny aversive threads into the memory of my nervous system.

As I earnestly looked for answers, I came across this paragraph in Dr. Suzanna Søberg’s wonderful book, Winter Swimming:

“The cold-shock response happens when cold water touches your skin…triggering an increase in heart rate and blood pressure. At the same time, the parasympathetic system is activated due to the ‘diving response’ associated with cold water immersion, which, contrary to the sympathetic nervous system, lowers heart rate and blood pressure. Could it be that there is a physiological conflict in the system during cold-water immersion? Yes, this could well be the case and explains what winter swimmers feel before and after the initial cold shock: hyperventilation, which gradually turns to normal breathing and feeling calm” (Winter Swimming, p. 76).

In other words, with cold water exposure, the stress system and the calming system can be activated at the same time — creating what Dr. Søberg later refers to as an “autonomic conflict” (Winter Swimming, p. 164). While most of us can re-regulate after an “autonomic conflict,” it’s generally a good idea to avoid it if you can. She even goes on to say that an “autonomic conflict” can be dangerous for people with underlying heart conditions.

So how do you avoid it?

Two-Phase Plunging

What I started realizing in my second week is that if I went in more slowly, I felt less panicky. As I kept plunging, I discovered that it was better if I plunged in “two phases.” So I started lowering into the water just up to the top of my stomach and would then wait there for 30 seconds to 1 minute (until my breathing and heart slowed back down). At that point, I would lower all the way down to my neck. This “two-phase plunging” was a game changer. It completely erased any feeling of overwhelm, panic, or hyperventilation. It also gave me a much-needed sense of control.

So why did it work?

Phase 1: Activating the Stress System

When I would enter the water up to the top of my stomach, it was clear that I was activating the stress system (based on my increased heart rate and rapid breathing). Adrenaline — which activates that first stage of a stress response — can turn on and off relatively quickly. So within a minute or so, it felt to me like the initial stress response had activated, peaked, and come back down. Which meant it was time for phase 2.

Phase 2: Activating the Calming System

Your ventral vagus nerve, when stimulated, activates the calming system. So where is your ventral vagus nerve? It wraps around your heart, lungs, upper esophogus, neck, and face — i.e., from the chest up. So instead of going in all at once and activating both systems at the same time — creating an “autonomic conflict” — I became super tuned into these two parts of my nervous system and only engaged one at a time. Activating my stress system and my calming system sequentially, rather than simultaneously, made all the difference. Once I regained a sense of control, the experience slowly started to train my brain that this is challenging, but not overwhelming — the perfect sweet spot for building confidence. And that’s what surprised me the most — how good it felt afterward.

Confidence, Motivation, Euphoria, Oh My!

Every time I got out of the water, I felt like I could take on the world. There was a surge of confidence that was unmistakable. The feeling was so much more powerful than I expected. But it wasn’t just a feeling, it was a feeling and a story. The story was, “If I just did that, what else could I do?” It made everything in my day feel easier. Writing? No problem. Cleaning the house? Easy. Inbox? Pffff. You know that sluggish feeling you get when you binge on social media? This was the exact opposite.

The “after-effect” of cold plunging is really why people do it. And it wasn’t just confidence — it was also increased energy, motivation, and even a feeling of bliss. For me, the euphoria usually lasted 1–2 hours in the morning after plunging, but the increase in motivation lasted longer. Specifically, I noticed that I had more energy at night after the kids went to bed. Dishes and clean up, even late into the night, didn’t feel overwhelming anymore. I also noticed other effects: I started falling asleep faster at night and waking up more rested, I felt more focused at work, and at one point in February, everyone in our house got sick except for me.

There’s a reason for all of this. Cold exposure has been shown to increase dopamine production (motivation), increase norepinephrine (focus), and boost your immune system. And, while it’s harder to measure, there were likely benefits to my metabolism as well. Cold plunging activates what is called “brown fat,” which in turn increases your baseline metabolism so that you burn calories more quickly.

With so much to be gained, how do you actually get yourself to do it? And is it possible to do too much of it?

Habituation: A Blessing And A Curse

Even though it was a delayed gratification experience — I had to do the hard thing first and the rewards would follow — I did start to look forward to it. In fact, when I paused at the end of the month, I started to miss it. The upside was so good, my body started to crave it. It’s not to say that I don’t feel that small feeling of anticipatory dread before I plunge now (I do), but that the feeling itself is smaller than the excitement I’ve trained my brain to expect based on the “after-effect.”

I was also able, to some extent, to get used to the cold — what scientists call “cold habituation.” Habituation means that our brain learns to decrease the response to something the more we do it. When it comes to the cold, this is definitely something you want — you want it to feel less painful, less shocking, and easier over time. In fact, while I could only stay in the water for 33 seconds on Day 1, I was able to stay in the water for 8 minutes and 22 seconds on Day 28. During my 30-day challenge (even with my “sensitive skin”), I was able to better tolerate the cold over time.

But when it comes to the “after-effect,” you don’t want your brain and body to habituate. You want to keep the positive “after-effect” strong. So as I went through the month, while I noticed myself “cold-toughening,” I did also notice a slightly smaller “after-effect” the more I did it. This is classic habituation — it cuts both ways. It makes hard things more tolerable and it makes good things less good. So what’s the right balance?

Settling In

Now that I’ve been through the 30-day challenge of cold plunging, I’ve settled into a more sustainable routine. I now do a 4–5 minute plunge or a 4–5 minute “cold shower cap” (at the end of my warm shower) 2-3 times a week. Again, I’m listening to my body and I might adjust this as I go. I’m trying not to do it so much that I over-habituate the “after-effect” but enough that I don’t under-habituate the “cold-toughening.” In other words, I want to make it a sustainable part of my life, so finding the right balance is key. This also aligns with recent research that suggests that 11 minutes total per week will give you optimal benefits of cold-plunging.

Playing the Long Game

If you’re new to cold plunging, this all might seem a little overwhelming. If so, start the way I did — by ending your shower with a quick “cold cap.” If you start with 15 seconds, then go up to 30, etc., you’ll find that you can handle 1–2 minutes in a matter of weeks.

By building up your tolerance slowly, you’ll not only start experiencing the benefits of cold plunging, but you’ll also lay a foundation to make it a sustainable habit in your life. In building up your tolerance slowly, you also won’t be tempted to quit — it’ll start to feel like a normal part of a healthy routine.

In the end, the most important lesson I’ve learned is that cold plunging isn’t a game of proving yourself. It’s a game of sustainability.

This article was originally published in Change Your Mind-Change Your Life.