Physical activity, including walking outside, can increase alertness by overriding adenosine buildup, potentially due to daylight exposure and endorphin release.

“but another way is just get outside and walk around be physically active some of that has to do with the fact that you'll probably get some daylight and daylight can be a stimulator of alertness as long you've told us and educated us on we also know that physical activity by itself can increase the amount of endorphins and dorphin and those are wake promoting”