Thermoregulation
A group of monks known as the Tummo are known to practice biofeedback meditation techniques that allow them to raise their body temperatures substantially.
The good news is a lower body temp may produce a longer life span.
The less good news is you’ll be uncomfortable in the pursuit of it.
I’d like to be an endotherm, like the Ostrich. Plus I think the Ostrich has an inbuilt appreciation for the cardigan.
Another consideration is kleptotherming like the penguin engages in.