As said earlier, there are more then one way to raise body temp. This second part will discuss involvontary raise of body temp.
But i will not discuss “fever”
Cold induced shivering thermogenesis: This is the when you start shaking like a leaf on tree. This kind of thermogenesis is very unpleaseant but necessary in the beginning of your cold Journey.
this type of thermogenesis uses glycogen, and it promoted browning of White fat(WAT) to brown fat(BAT)
why is that important? Because Brown Fat is KEY,
Non shivering thermogenesis(NST): also known as Brown Adipose Tissue(BAT) activation. This is the kind of thermogenesis where you don’t shake, you BURN.
The BATivation is considered the holy grail of thermogenesis, you burn white fat to stay warm, (the more you undress, the more fit you get).
The way to Increase BAT is to subject yourself to cold environments more frequently, example: taking ice baths, walking around with less clothing, taking off your socks. etc etc, there are many ways, and just a small increase in cold subjection makes a big difference in how you percieve cold.