Two or three minutes under cold (or at least colder) is an awesome morning wakeup IME.
The effect is probably mostly Mammalian diving reflex, which is triggered by colder-than-21°C water contacting the face, with other factors (such as showering your whole body) much less relevant.
The effect is probably mostly Mammalian diving reflex, which is triggered by colder-than-21°C water contacting the face, with other factors (such as showering your whole body) much less relevant.
Seems to have a lot more effect when it’s a shower, not just cold water on my face.