About 10 weeks ago, I did a 16-hour snow hike in Newfoundland (off-topic: insanely gorgeous country!).
The outside temperature was still very warm for November, with highs of -5ºC / 23ºF and lows of -10ºC / 14ºF.
I wore multiple layers, as I was prepared for remote possibility to stay the night on the mountain, should I become too tired. For great majority of the hike (10-12 hours) I had all 3 layers open, as it was simply too hot (just -5ºC / 23ºF) and I was sweating like a pig, especially the middle part of the ascent, before I reached the steep gully, where the wind picked up and I eventually zipped all 3 layers (though only for the rest breaks). My best estimate is that the wind-chill before summit was around -13ºC / 8.5ºF, still far from cold, but at least more comfortable for hiking than the "hot" -5ºC / 23ºF.
The problem now is that my internal thermostat / cold resistance got somehow readjusted during the hike, by roughly 4-5 degrees Celsius.
As an example, the default in-room 20ºC / 68ºF now feels hot. Not for 5 minutes; all the time. It's more than 20ºC / 68ºF everywhere I go indoors — office or home. I've found out that the comfortable room temperature wearing T-shirt and shorts is now around 18.5ºC / 65ºF, which is insane for everybody else.
My best guess at this point is that my body 'thermostat' returned back to the winter values I was used to 20 years ago back in Europe, with highs of -15ºC / 5ºF and lows of -25ºC / -13ºF.
But, it's been over 10 weeks since the hike. There must be a switch I can flip back!
Any ideas how to readjust it back? Or at least do things differently for next snow hike?
Perhaps the water intake is to blame? I underestimated the hike (and I quite honestly did not expect excessive sweating at -5ºC / 23ºF) by ±6 hours, so those 6 litres of water (I need 1 litre per 2 hours in winter, much much more in summer — hence the preference for winter hikes) I was carrying up (though I left few additional bottles in car, and I drank half litre right before start of the hike), got consumed very fast (and I basically ended with 1 last litre for last 6 hours — though that was descent, so much less water was physically needed).