I have to wonder if there's a lactate connection here.
We now know that type 1 myocytes (skeletal muscle cells) donate lactate to type 2 locally - with a good bit of that ending up in the circulation. When it gets to the liver, some of it is converted back to glucose.
Thre's also some research showing there's a similar lactate 'shuttle' between astrocytes and neurons (for those unaware, astrocytes have parts of their cells wrapped around the capilaries that are part of the blood brain barrier - so they have more immediate access to both glucose and oxygen than the neurons). Lactate can pass the blood brain barrier. So if there's a surge of lactate in the circulation...
Also, if you don't know what lactate is, suffice it to say that your mitochondria can use it as an energy source. When your cells take in glucose, it has to be broken down in the cytoplasm (glycolisis - multiple steps) before the mitochondria can use it. This nets a couple of ATP per glucose, but compared to the 30-ish a mitochondria can make that's not much. Lactate can be used with minimal change.
For anyone interested in lactate and the 'shuttle between type 1 and 2, I'd suggest Peter Attia's conversation with George Brooks "#312 – A masterclass in lactate": https://peterattiamd.com/georgebrooks/
I'd already known about the astrocyte->neuron shuttle so when he mentioned the one between muscle types a bell went off in my head...
Also, it's lactate, not lactic acid (listen to the podcast).