For me it’s only a semi-conscious pre sleep state, but it helps significantly.
Do this if you get tired while driving too. It’s a life saving practice!
(And no, driving tired isn’t always due to bad nights sleep. Glucose spikes can be dangerous even if you sleep well at night.)
I hope your Nebraska highways have some exits/side roads you can pull into. I’ll do that sometimes, or find a town and park a gas station somewhere.
Glucose spike is referring to the thanksgiving dinner effect where you get tired and need a nap after eating. Feeling tired after lunch. Etc.
It can happen after almost any meal, even while well rested, etc.
There’s ways to reduce the spikes but afaik once you get the spike, nap is the best solution.
Coffee can help for some type of tiredness, but sometimes it’s not enough.
I’ll do 15-20 min nap increments. Sometimes one nap isn’t enough, I need to rest longer. Thankfully, I can always tell when the one nap is insufficient before getting on the highway again.
A notable example I remember are the United Nations’ live interpreters. They can only interpret a live conversation for only about 45 minutes before they have to switch off with a new interpreter because the error rate just exponentially goes up due to mental fatigue.
That said, I have had the unsettling thought that the brain is never really “off” during your lifetime. With computers you can restart them, but your brain keeps going, even when you’re sleeping. So I think we should be nice to our brains.
That might be enough to recharge you to a normal level after something particularly taxing.
It's not enough to restore you completely, and certainly not after an entire day's worth of activity.
And there's so much more to sleep that you're missing, like consolidating memories, muscular coordination habits and patterns, etc.
However, research shows that long term learning etc, as well as critical decision making, are impaired.
My anecdata of 1; I prefer 6-7 hours of sleep, but during some expeditions, I'd be lucky to get 2-3 hours before a summit attempt of 12-18 hours (leave at 1-2am, return to high camp by 3-4pm, pack up and head down to a lower level for safety). For safety, I make sure to practice all the skills required (rope, carabiner and knot handling) so these are "routine", and not require more cognitive effort to "figure out".
A funny story during an expedition: a friend couldn't lift his foot whilst we were all preparing for some ice traverse - it was stuck for some reason, we all stood around wondering why, and we finally realised I was standing on one of his crampon straps. I swear it took us 10mins to figure this out, a result of sleep deprivation, high elevation, being swathed in layers of clothing, and general fatigue.