Exercise

A 2007 study found acidification of our blood increases excitability of orexin, whereas alkalinization depresses it.  (R)

Anything that increases Hydrogen Ions/acidity or CO2 will increase orexin. (R)

Exercise increases both CO2 and lactate, which makes our blood more acidic.

Interval exercise especially leads to a surge in lactate, which you will read is important for exciting orexin, regardless of acidity.

Exercise can increase wakefulness even without the orexin system, so it’s good anyway. (R)

Even the increases in CO2 in the atmosphere from increased pollution can increase orexin activation, which means people have slightly more orexin activation than in the past (all other things constant) (R).

(The effects of pH involve acid-induced closure of leak-like K+ channels in the orexin cell membrane. (R))

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