I looked up some more information on glucose metabolism after reading @Eric’s reply to @arnolfo after he experienced an intense period of low BG after activity. 
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Thanks for sharing, @CatLady. That is a good summary.
A few things I mentioned on the other post that are referenced in the link you shared, and are important to highlight:
Skeletal muscles are unable to release glucose
Yes! Very important to highlight.
One way of remembering this is that muscle glycogen is not shared! Your legs don’t help your arms when they are doing bench press. And your arms don’t help your legs when they pedaling the bike up the hill.
And neither your arms or legs will help your blood sugar.
So just remember it in this way - muscle glycogen is not shared!
And something to clarify to this part of their writeup, which I think was not 100% accurate in the way they stated it.
They said:
In humans the majority of glycogen is stored in skeletal muscles (∼500 g) and the liver (∼100 g).
The amount you can store in your muscles depends on your size and the size of your muscles.
An small child will not be able to store as much muscle glycogen as a huge lumberjack. A body builder with huge muscles can store more than a ballerina.
So that “~500 g” reference is not entirely accurate.
But… the storage in your liver is pretty much consistent for all people, regardless of size. It ranges from 90-110 grams. So you can say that 100 grams is pretty much the same for everyone - lumberjack or child.
So yes to the ~100g they referenced, but no to the ~500g they referenced.
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Yeah, that’s what I was thinking!
Wow! I never thought about that at all! 
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I found this paper on muscle glycogen depletion and insulin sensitivity quite interesting.
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Great another fact my brain won’t forget! It will probably come out at a dinner or potluck based on the conversation in furtherance my “nerd” quotient! People look at me in wonder and comment, “There goes Tom again! What BS!” It’s ok, we’ll know its true!
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@TomH
Here is another good one to remember.
Do you know the 7 tissues /organs that do not need insulin for glucose uptake?
Easy to remember with the mnemonic “Brickle”
B for brain
R for RBC
I for intestine
C for cornea
K for kidney
L for liver
E for exercising skeletal muscle
Most of these make sense if you think about them.
Our brain needs a constant fuel supply. It needs to be fed constantly, even if there is no insulin available. Otherwise we diabetics would be in trouble. So it can get glucose without insulin. It does not use insulin dependent glucose transport, it mostly uses GLUT1 and GLUT3 to get its glucose. (Fun fact - the brain uses more glucose than any other part of the body!)
Same holds true for red blood cells, they need a constant supply.
Intestine - think about what would happen if it relied on insulin. If it relied on insulin, then the absorption of glucose from meal to meal would depend on our insulin levels. And sometimes it would hog the whole meal.
Cornea - not totally sure why on this one, other than maybe our sight would be affected. 
Not too sure about cornea. Sorry!
The kidneys help maintain our glucose levels by filtering and reabsorbing glucose. If they needed insulin to absorb glucose, they would not do a very good job!
And the liver also absorbs and stores glucose and releases it when needed. Same as for the kidneys, if it needed insulin to absorb glucose, it would not do a very good job of doing this.
And for exercising muscle - well, this one is not easy to explain and not well understood. There is a level at which exercising muscle can do that, but it is not as easy as going for a walk. This one would need another post.
So there you go. Another great subject for conversation if it comes up.
Just remember “Brickle”.
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The outer layer (epithelium) of the cornea has no blood vessels – which, you’re right, would affect the vision – so it can’t get glucose from blood. But, like the brain, it uses GLUT1 for transporting glucose, in this case from the aqueous humor – the fluid between the cornea and the lens.
Now if I can similarly set free the other 40,000 or so bits of trivia that clutter my brain, maybe I’ll remember where I left my keys.
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