Good evening,
Firstly, I am going to ignore those on ketone diets as I don't understand the ketone depletion process at all, although glycogen and ketones can be seen as functionally interchangeable to a large degree when all is normal, depletion is not normal.
It turns out that the body has a glycogen depletion prevention mechanism and I suspect that how this works will be at least part of the reason for different experiences.
In normal circumstances the brain extracts glucose from the blood to power it, the muscles convert their glycogen to glucose when needed to supplement their energy need when it can't be supplied from blood glucose.
When the muscle glycogen is depleted all of the required glucose is pulled from the blood stream and the liver responds by increasing the conversion of liver glycogen to glucose and releasing it into the blood. At some point a mechanism determines that the glycogen conversion rate is too high and reduces/supresses it.
There is no mechanism to tag glucose in the blood for use by the brain only or the muscles only.
Pure supposition here but when and by how much this suppression takes place would seem likely to alter the individual's experience.
- Only partly suppress the increased rate and do so early would see the individual getting hints that all is not well.
- Barely suppress the rate and only do so late on would see the individual going from all's fine to not enough glucose to move or think within a very short period of time.
Bye
Ian
