To tell you not to run around if caught in snow- exercise cools you down

[Nimbostratus100]

I am quite alarmed at the level of ignorance shown about this, so just in case anyone here gets caught in snow today

Please don't exercise to warm up - or tell your children to - this cools you down and leaves you vulnerable to hypothermia

Insulate yourself as well as you can, and huddle as close together as you can instead.

You might need a brolly!

@ItsCalledAConversation 🤣

@ManchesterGirl2 I'm guessing it's because it causes vasodilation. So as you exercise you get warm, but your body dilates all your surface blood vessels to cool you down again and makes you more susceptible to hypothermia.

How interesting - this is counter to what I experience but I've never been in a life threatening cold situation. I get really chilly sitting at my desk too long and find a brisk run up and down the stairs makes me feel warmer.

Exercise does warm you up though.

The problems come when you run out of energy and have to stop exercising. The warmth you generate is your body burning its fuel (food), so the underlying source of the warmth is the fuel.

Having sweets on you, or some other energy dense food, will help keep you fuelled, active and warm.

Please evidence your claims.

Exercise does warm you up, I think what you are trying to say is when exercising in cold conditions and you sweat the sweat freezes

Breathing in freezing air cools your core too. However, I doubt todays temperatures in the UK are low enough for that to be a real hazard.

I clicked here because I thought 'that doesn't sound right'

Is it because initially it warms you up but then because of that your body naturally does things to cool you down like sweat? And that's when you risk hypothermia because now you'll be very cold where at first you were indeed very hot?

I went for a run in the snow last night - it took longer than normal but after 2 miles I started getting the feeling back in my toes and fingers so it definitely warmed me up!

This is all I found too. That sweating can be dangerous in cold survival situations.

Over a longer period, exercising without replenishing your fuel stores will cool you down.

But moderate exercise (e.g. steady walking), coupled with energy dense food to give your body a source of fuel to burn, is not going to give you hypothermia.

(Source - I do a lot of winter sports, including ice climbing, in temperatures well below what you are likely to experience in a London park.)

I've just had a quick Google and everything I've read says that exercise generates lots of heat, however sweating can cool you down when you stop and cause you to be too cold so you should dress in plenty of layers.

Not sure why you're posting this health warning but hey, you do you.

Kids are going to run in the snow forever and a day, no changing that.

Exercise makes you feel warmer because it causes blood to flow to your extremities and provide energy for the movement, taking heat(energy) away from vital organs. Heat is lost through extremities more quickly because of high surface area, and the burning of energy also means you have less energy to generate heat after the exercise. So yes it does cool you down internally and risk hypothermia. But makes you feel warmer. So fine if you are caught outside for a short period trying to keep warm, not in a dangerous situation as OP said.

Its the same logic about having brandy to warm you up, makes you feel warm but actually cools the body internally.

Also, exercise doesn't have to involve lots of sweat. Steady walking is enough to keep most people warm without turning them into a sweaty mess. The OP is making the mistake of assuming that exercise has to be vigorous.

I googled and every link I clicked on said this basically.

So you're wrong, OP🤷‍♀️

“It is agreed that there are potential risks associated with cold air exercise (respiratory problems, hypothermia, and frostbite)1 and recommendations such as cover your mouth or do not exercise in temperatures less than -15℃“

Like I said above, it isn’t cold enough in the UK for it to be a problem.

www.ncbi.nlm.nih.gov/pmc/articles/PMC5705483/#:~:text=It%20is%20agreed%20that%20there,15%E2%84%832%2C3%20exist.

Bear Grylls is that you?

www.mayoclinic.org/healthy-lifestyle/fitness/in-depth/fitness/art-20045626

This supports the op. But I don't know what kind of weather it means.

Dont be daft, Bear loves a good roly poly in the snow!

Just did exactly the same and got exactly the same results. I know it's just Google and not scientific or anything, but even my own personal experience of running in icy/snowy weather confirms what good old Dr google says!

Basically exercise will make you warm but lose heat. It also might give you a false sense of warmth and then you take off more layers leaving you get cold. But I'd hope anyone who's caught in the snow wouldn't be for hours and hours.

In theory you're right OP, but I know literally no-one who, if stranded outdoors in the snow (how?) would suggest running around rather than huddling together to keep warm.

So if exercise is dangerous, why is the body’s natural response to cold to shiver?

muscle activity= heat. That’s why we shiver in the cold, to raise the core temperature and stop us freezing.

you’re more likely to get hypothermia from not moving around and allowing your temperature to drop.

Shivering is a short term fix, and it's one of very few mechanisms the body has available.

The underlying warmth always comes from the body's energy stores - that's what moves the muscles, so the key is to stay fuelled. Sugary sweets etc., whatever delivers fuel to the muscles in the fastest way.

Yes, exercise warms you up.

I think what the OP might mean is that if you have been exercising in the cold (and it's temperature, not presence of snow that matters) and then stop and remain in the cold, then you might find yourself in trouble.

But if you go for a good frolic in the snow, then make your way back to shelter during the time you are naturally returning to normal body temperature, you'll be fine.

But if you're trapped outside, things like cold sweat will chill you, and could lead to your body diverting heat to key organs, leaving extremities vulnerable, and (if extreme) that means you become clumsy, eventually get brain fog and can act in ways contrary to survival.

There was a really good set of RI Christmas lectures on endurance and the science of survival

{{https://www.rigb.org/explore-science/explore/video/back-brink-peak-performance-2007]]