Jumping into cold water can stop your heart

ffanf2 about 5 hours ago 33 commentsRead Article on jorgenmelau.substack.com

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mikestew•about 5 hours ago

I jumped into icy (literally) water with a few high school friends many decades ago. I still remember that it felt like my heart stopped when we jumped into the water. Now I find out that it can literally happen. Good thing we were young cross country runners in good shape. (Yes, I read the part that athletes aren’t immune.)

rick_floss•24 minutes ago

Had to look up the term: Winter swimming. Avantouinti in Finnish: https://en.wikipedia.org/wiki/Winter_swimming?wprov=sfti1

Very popular. Never have I heard of anything other than health benefits from this.

time4tea•22 minutes ago

Float to Live

https://rnli.org/safety/know-the-risks/cold-water-shock

dewey•about 5 hours ago

Living in the alps this is something you hear from time to time, people going hiking and jumping into ice cold mountain lakes after and dying on the spot.

cannonpr•about 5 hours ago

I’ve been swimming both winter and summer since 1ish years old though less so post 30’s due to locale, and I’ve never had much of an issue with gasping with cold water impact, sure there is an urge but I’ve always suppressed it without issue. Yet literature is adamant you can’t ? I wonder if it’s habituation or just a biological quirk.

mikestew•about 5 hours ago

TFA mentions habituation as a mitigation:

”Habituate. Five or six short cold-water dips over a couple of weeks will cut the cold shock response roughly in half, and the effect lasts for months. This is probably the single most underused safety intervention in open-water swimming.”

Cpoll•about 2 hours ago

I've experienced a similar adaptation when experimenting with cold showers. In that sense it was somewhat of a detriment; the cold became less invigorating but just as unpleasant.

borski•about 3 hours ago

Habituation. You’re effectively trained.

buildbot•about 4 hours ago

How common is this? In scouts we often did this, jumping into alpine lakes where you could see a glacier melting across the water.

We were also told that to treat heatstroke tossing someone in the lake and then treating for shock was somewhat preferable…

orbital-decay•29 minutes ago

Ice hole swimming is common where I am, and each year some people die from fainting in the water due to entering too rapidly without training. A few years ago there was a case of an experienced woman losing consciousness and drowning in front of her husband and kids. Not sure about heart attacks in particular, I think you need an underlying condition to have an attack.

PyWoody•about 4 hours ago

Very common.

There are quarries around where I am that have signs posted to not swim there in the Spring. Yet, like clockwork, 1-2 people drown each Spring.

sigmoid10•31 minutes ago

That's a different kind though and only mentioned on the side in the linked blog. If you don't know what you're doing and you jump into freezing water for the first time, chances are that you'll breathe in water. Happened to me as well. Let me tell you, it really sucks. If you're unlucky, this can definitely be enough to make you drown. But with training you can easily overcome this problem. I have jumped into arctic waters many times since then with zero issues. What the blog claims, is that there is a vague, general physiological risk from some kind of mixed response targeting your heart. I have to say I've never heard of this before (except for people with pre-existing conditions) and the blog does a poor of explaining the biology beyond high school level anecdotes. It also cites zero sources. So while there is a risk, it is not what you might think after reading OP's link.

x-n2o•about 1 hour ago

“ Cold water on the face, together with holding your breath, sets off what is called the diving response. Your heart slows down. The blood vessels in your arms and legs squeeze shut” - aka. The Mammalian Reflex. I thought it did the opposite - blood pressure goes down thus your vessels expand.

alehlopeh•about 2 hours ago

> Michael Tipton described this sequence in 1989, and it has not really changed since

How exactly could the human body’s response to cold water shock change since 1989?

> This is how strong pool swimmers drown ten meters from a boat.

They drown 10 meters from the boat when they first hit the cold water? Did they jump 10 meters?

PufPufPuf•about 2 hours ago

1. Our understanding of the underlying mechanisms may change over time.

2. They don't die instantly after hitting the water.

lexicality•about 2 hours ago

> How exactly could the human body’s response to cold water shock change since 1989?

microplastics

kakacik•about 4 hours ago

When I was doing road trip through Iceland in may cca 10 years ago, I ended up in northern part in some sort of camping where there was just my tent. Plus surprisingly some local kids were on some school trip.

I dont even recall how the heck I ended up with them in their trip bus, going to some canyons. Everybody got wet suit (around 5mm), and we ended up jumping from cca 5m cliff down to river. There were still patches of snow on the banks and water temperature was corresponding, most inland of Iceland had still metres of snow, only ring road was cca passable.

Most boys and me kept jumping and climbing back up, it was almost same cold in wet wet suit next to river than swimming in it. Most girls shivered like crazy, blue lips and all.

These were icelanders, around 13 years old, tough as it gets re cold. I recall their teacher explained it to me that in the past, as test of maturity every boy (not sure about girls) had to swim across big fjord somewhere around Husavik IIRC as sort of rite of passage, at least 3km width.

Glad nobody had heart stopped, that river was murky and strong. Every jump into that cold was like an electric ahock to mu body

elabajaba•about 3 hours ago

> These were icelanders, around 13 years old, tough as it gets re cold.

Iceland has a famously mild climate, even during winter their average temperature is still above 0C.

locallost•about 5 hours ago

I learned to swim at an older age and my instructor told me this because at the time a person died screwing around in a boat with his family. Jumped into the water on a hot day and dived for fun, but never came back up.

deadbabe•about 3 hours ago

Is there a way to jump into cold water but also ensure you don’t stop your heart?

AngryData•about 1 hour ago

Jump into or heavily splash yourself with cold water more often to better train and regulate your body's response.

borski•about 3 hours ago

Spray yourself with cold water first and minimize exposed skin. That’s literally what TFA says.

FpUser•about 4 hours ago

Back in the old USSR we would go to banya (Russian Sauna) and it had creek right flowing close to front door. we dug in a huge barrel so it formed a tiny pond of really icy water. So we sit in a sauna for a while and then jump into that icy pool and then cycle repeats. One barely feels cold after getting out of sauna and into the water. More like some exciting sensation.

senordevnyc•about 4 hours ago

Jesus, can’t anyone write their own fucking short blog post anymore??

gruez•about 4 hours ago

Don't worry, the author has this blog post in book form as well, complete with AI-generated images!

https://jmelau.gumroad.com/

Esophagus4•about 4 hours ago

The internet is a content beast, and the beast must be fed.

owaiswiz•about 3 hours ago

> Not in the middle of the fjord. Not halfway across the channel. The first three minutes

Easiest tell

dalmo3•about 1 hour ago

At this rate Lee Child must have already secretly invented AGI.

sjducb•about 3 hours ago

Genuine question, why is this a tell? It looks like good dramatic writing to me.

Cpoll•about 2 hours ago

Check out https://en.wikipedia.org/wiki/Wikipedia:Signs_of_AI_writing

That structure is common. "Not X, but Y" plus "Rule of three." It's not that humans don't ever use that structure, but it's rare outside of LLM output.

Any single data point doesn't mean it was LLM generated, but they add up.

fourthark•about 1 hour ago

> You gasp. You hyperventilate. Your heart rate jumps. Your blood pressure climbs. All of this in a few seconds.

There's something especially creepy about AIs talking in the second person about biological processes they don't experience.

mmanfrin•about 3 hours ago

Well its just copy to sell an ai-generated minibook.

jareklupinski•about 4 hours ago

> consider becoming a free or paid subscriber.

not when money is involved