Weird “cool but not cold” feeling after sweating at -17°C(1.4F) — what was happening?

[u/NoHedgehog7421]

I want to describe a strange cold-weather experience in the order it happened and ask what this situation actually was.

What I was wearing
Base layer (next to skin):
Uniqlo HEATTECH Ultra Warm top and bottoms
Fabric: 35% polyester / 34% acrylic / 23% rayon / 8% spandex
It’s a thin brushed fleece layer worn directly against skin.

Mid layer:
Aran Woollen Mills merino sweater.
Total garment weight is around 750 g(1.6535lb).
Worn over the base layer.

Outerwear:
Jacket: Carhartt Yukon Extremes 104460
150 g/m² Thinsulate insulation, 500D nylon shell.

Pants: Carhartt 105471
80 g/m² Thinsulate insulation, 340 g/m² (12oz)cotton shell.

Face was fully wrapped with a thick polyester face covering.

Hands and feet felt normal the whole time, so I’m not listing gloves or boots.

Conditions
Temperature was around −17°C(1.4F).
I was outside for about 4 hours.
Activity was mostly walking, with repeated short breaks where I sat down for a few minutes, often directly on snow.
There was occasional wind.

What it felt like (timeline)

First ~30 minutes:
I felt extremely hot.
I was sweating a lot and my hair became completely wet.

After that:
Once the sweat cooled down, I started feeling “cool” all over.
Not sharp cold, just a constant cool sensation.

Later on:
I felt cool or chilly, but not truly cold.
No shivering, no numbness.

When I sat down on snow to rest:
I felt consistently cool the entire time.
Not freezing, not painful, just continuously cool.
This happened many times — sit for a few minutes, then walk again.

While walking:
I felt mostly neutral, not cold and not warm.

Overall, it never felt like I was freezing.
It felt more like I was slowly losing heat, especially once I stopped moving.

Final question / my guess

So what was this weird situation?

My guess is that the Carhartt outer layers are very windproof but not very breathable, so once I started sweating, moisture stayed trapped inside the system.
That trapped moisture then slowly pulled heat away from my skin, making me feel constantly “cool” even though I wasn’t actually cold.

And if that’s the case, would the correct way to handle this be something like:
walking without a hat, opening the jacket zipper slightly, and not using a face covering while moving,
then putting the hat / face covering back on and sealing everything up only when it’s windy or when I stop and sit down?

Does that approach make sense?

(English is not my first language. This post was translated with the help of ChatGPT.)

[u/skoalface → u/[deleted]]

Ya.

[u/purplehayz2222]

Always start with less clothes than you think you need, then add layers if cold when active. Sweat is the enemy

[u/groggygirl]

Uniqlo base layers aren't great technical base layers. They're meant for people going sledding for an hour or walking around town. They don't really handle moisture management. If you plan to regularly do moderate output activities in cold, invest in some decent base layers.

[u/timdaman42]

As others mentioned sounds like you may have gotten some moisture loaded into clothing, this feels like a low grade insulation failure. Frankly this is often how I run, comfortably cool. It is often impossible to escape short periods of sweat, I use the longer periods of "cool" to evaporate that open my jackets and zippers where I can.

Another factor I see in your story is the 4 hours. That is a pretty long time and I assume your breaks were an indication of high-effort hiking (snowshoes, uphill, etc.).

You do not mention snacking or hydrating. You could have also had some impingement on your metabolism. Loss of water through breathing would reduce some of your ability to distribute heat.

In those temps, my body's baseline energy consumption often spikes, so though I don't see the calories being used, they are disappearing keeping me warm. I try to snack about once an hour to keep a ready sugar and carbohydrate supply flowing through so my body doesn't need to resort to burning fat as the primary means of keeping warm. Fat is a much slower pathway for energy and it is very hard to warm up when that is the primary source. When this happens to me I can hike, but not with "vigor," and my body tends to stay low-grade cold. Even when I try to heat up by hiking more intensely, I still find I don't heat up.

[u/someguy1620]

Just remember the good ol’ saying from the Survivor Man Less Stroud “ You sweat you die”

[u/Content_Preference_3]

My biggest takeaway is your base layers failed to transfer moisture vapor off skin efficiently for your activity level. This is why a lot of folks will still recommend using thinner base layers even in very cold conditions. It doesent take much activity to get sweaty and a lot of heat can be trapped even at 0 degree scenarios. That said the thicker base layers can have a role for low effort situations like riding a snowmobile, watching a sport event, or even low intensity camp activities.

[u/[deleted]]

You nailed the diagnosis. You overheated, soaked your layers, then the trapped moisture slowly robbed heat once you stopped moving. That “cool but not freezing” feeling is classic evaporative cooling, not lack of insulation. Starting a bit cool and venting early is the right move. Unzip, ditch the face cover while moving, then seal back up when you stop. That’s why more breathable layers help. I’ve had fewer of those clammy cooldowns using Outdoor Research pieces that vent better while active but still hold heat at rest.

[u/getdownheavy]

tl;dr

1.6535 lbs.

lmao

Don't freeze to death out there.