I’m kayaking on the Bay of Fundy in late October. The air is cool. The water is cold — about 12 degrees C at this time of year. The massive tides mean that even in summer the bay is cold. After pulling the boat up on shore, I walk out into the salt water up to my knees, go back to shore, then walk back into the water and start swimming.

A practiced, even clinical approach. Still, it’s a shock.

I’ve been doing this for a few weeks since the nights cooled off, so I am starting to adapt. Lately, I’ve learned, by trial and error, that if you keep your head out of the water at least for the first few strokes it’s less of a shock. But it’s still friggin’ cold. Back on shore, I soak up the sun. That wasn’t so bad, says one part of my brain. Yes, it was, says another.

Later in the week I go kayaking on the lake. It is late afternoon, the air is 20 degrees, extremely warm for late October, and the sun is coming out from behind the clouds. On the way back I stop at a small beach and use my new routine to ease into the water. It’s not as cold as the ocean, I tell myself, managing 30 strokes out and 30 strokes back. Because the air is warm and there is no breeze, I don’t get a chill when I get back on the beach.

Cold water swimming is catching on and science is trying to keep up.

This brief exercise is not the hardcore stuff advocated by Dutch athlete Wim Hoff, who has become a cult hero. In winter he sits or swims in ice-cold water. He sits, walks, and runs in the snow, in his bare feet, wearing shorts and no shirt. Over the years, he has developed assorted breathing exercises and meditation techniques.

Science has gradually caught up with Wim Hof, showing how the body has a host of healthy responses that kick in once you practice his methods over the long term. One key is that exercising in the cold encourages you to breathe more deeply, which improves your absorption of oxygen and calms your mind by slowing your brainwave patterns. See article: The Wim Hof Method: Boost Your Health with the Iceman’s Technique

This is the opposite of the high-powered caffeine- and cortisol-fueled experiences so many of us enjoy while sitting for hours staring at computer screens. Our breath is shallow and quick. We don’t exhale deeply, so we retain CO2 and therefore don’t breathe in enough O2. Over the long haul, this is hard on the cardiovascular system and other parts of human anatomy.

Indeed, there are many links between breathing patterns and physical and mental health. Practicing conscious breathing techniques has long been a part of Eastern meditation and physical routines such as Yoga. See article: 7 Ways to Practice Breath Work for Beginners

KIDS ARE COOL

As you practice experiencing the cold, it gradually gets easier. Your body gets better at adjusting to the change in temperature. You become more like the kid you were at age 5 when you could run around in the snow without a jacket, at least for a while.

On the other hand, one of the first things kids discover as they start to explore the world is: “Don’t touch that flame! Fire hurts – a lot!” So does the cold, with a burning sensation strangely similar to experiencing extreme heat. Caution around extreme temperatures is a deep reflex programmed into our biology by millennia, even millions of years, of hominid evolution.

We stay out of cold water the same way we avoid any apparent danger. We are creatures of habit, and for good reason. As evolutionary biologists like Mark Pagel have discovered, the brain likes to do what it did yesterday. The reason is simple: the body was alive yesterday and the main job of the brain is to keep the body alive.

Some of this is primitive stuff. The reptile brain, as it’s sometimes called, can move fast and over-ride the thinking brain. When you get low on oxygen, which can happen in seconds, you immediately gasp for air. Your finger recoils from a flame or a hot stove. No thinking required.

Indeed, the brain needs to keep the body within a very narrow range of key parameters. The lower brain runs the autonomic nervous system that manages the essential processes we rarely think about: breathing, thirst, hunger, and the need for rest and sleep. Then there’s that primal urge we call the “sex drive.” Sounds like a car ad. Indeed, advertisers ignore it at their peril.

Ambient temperature is one of the brain’s main concerns. We thrive only within a very limited temperature range. That’s why when we dip our toe in cold water, our body and brain get a strong signal. Danger! Our reptile brain intervenes to keep us alive.

Turns out that challenging your personal temperature comfort zone helps you maintain your internal thermostat. “Homeostasis” it’s called. The reason older people can’t tolerate much temperature change is that they rarely exercise; they are usually sitting in a chair at room temperature. Their bodies don’t have to keep returning to that thermal sweet spot. They lose the ability to self-regulate.

TAKE IT EASY

Still, cold water and even cold air can kill you. A sudden immersion in cold water and your body taps into this deep reflex where you involuntarily open your mouth, allowing water to flood into your stomach and eventually your lungs. Divers and offshore employees practice a long time to overcome this deep reflex.

Immersing yourself in cold water — or turning the shower setting on cold (or just colder) — triggers some of these same responses. As in all things, start gradually. Any shock to the system can trigger a physical reaction, including a heart attack, even among the very fit. You could have an underlying health condition and not even know it. See your medical practitioner before you start.

SOURCES:
Wim Hof Method: Cardiovascular System
Wim Hof Method: Dangers of hyperventilation and cold shower?
The Wim Hof Method: Boost Your Health with the Iceman’s Technique
What is Wim Hof Method breathing?

If you enjoyed this article, check out the link between sleep and wellness and this article Scientists: Swimming Fights Ageing

David Holt is the editor of Silver magazine.