your body is gonig with the path of least effort in order ot survive(read effort as: using resources)
the body doesnt know how long it has to be exposed to the cold, so it goes into survival mode.
its easier ot trap heat where its needed than to raise the temperature
the latter requires a lot of energy, energy you might not be able ot spare in order to mantain body functionality, while the 1st only requires controllnig bloodflow ot the vitals parts.
Latest Answers