ostermayer on Nostr: People feel invigorated after an ice bath because cold receptors in your skin trigger ...

People feel invigorated after an ice bath because cold receptors in your skin trigger sympathetic nervous system activation. Plasma norepinephrine and dopamine spike within seconds since your physiologic response is to "get out as fast as possible"

Then your pituitary gland pumps out beta-endorphins to bind opioid receptors to counteract the pain of the cold exposure (just like a runners high)

Vasoconstriction shunts blood to your core. When you exit, peripheral vasodilation creates a surge of oxygenated blood to your muscles and brain.

Your cognitive override of all these systems trying to get you out of the bath is fed by a later dopamine reward and your normal warm environment then feels like a luxury.