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Exercise effect on blood sugar - fed vs unfed


This is the first I have ever heard of EPI. I had to look it up.

https://pancreasfoundation.org/pati...ncreas/exocrine-pancreatic-insufficiency-epi/

The only symptom I have is weight loss without trying. I am a bit too thin. I don’t have any gastrointestinal discomfort, fatty stools, etc.

I also of course have an issue with my blood sugar regulation that I am still trying to understand.

My doctor won’t even order a fasting insulin or c-peptide test. I am looking for a new doctor.
 

I think you may not be entirely correct.

As I understand it when you are keto adapted you body burns ketones directly, which are produced in the liver from fat.

There are a few areas (including part of the brain) which can't burn ketones so the liver supplies glucose through gluconeogenesis.

Happy to be proved wrong.
 
I wouldn't say wrong, but you do seem to have your wires crossed the OP is talking about carb loading before exercise.

That has nothing to do with being keto adapted.

The bit I picked up on was "I think you might be getting confused there (or I am) muscles don't tend to burn fat ketogenesis but rather they replenish there glycogen stores from the glucose in the blood stream. When we say "burning fat" we realy mean breaking down fat stores into glucose"

My understanding is that when burning fat we break down fats into ketones, which is why you are likely to find ketones whenever you lose weight, and often overnight when you are effectively fasting.

Getting glucose from fat is a complicated energy pathway and not that common.
 
breaking down fat stores into glucose
You are right it's not possible for body fat to be converted directly into glycogen, but it is possible for fats to be indirectly broken down into glucose, which can be used to create glycogen.

The body breaks down fats into glycerol and fatty acids in the process of lipolysis. The fatty acids can then be broken down directly to get energy, or can be used to make glucose through a multi-step process called gluconeogenesis where amino acids can also be used to make glucose.

Getting glucose from fat is a complicated energy pathway and not that common.
It's not that anything your saying is wrong Grey, is just context. I'm not talking about using ketones to power the muscles but breaking down fat stores to create/replenish glycogen stores in muscles.

It is a "process" but that's what were talking about the benefit it of that process (weight loss) opposed to carb loading before exercise (no weight loss but good blood glucose control).
 
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When I eat carbs (even a small amount) before exercising, my blood sugar after exercising is far below what it was before I ate.
(e.g. 90 > 105 > 70)

When I exercise after not eating for at least four hours, my blood sugar drops much less (or,rarely, even rises a bit).
(e.g. 90 > 85)

I guess the carbs trigger the pancreas to produce insulin but it is more than needed since the exercise both increases insulin sensitivity and burns up the carbs I just ate.

When I don’t eat, the pancreas isn’t triggered to produce much insulin, so the muscles just use glycogen they have and the liver releases glycogen, but since insulin wasn’t triggered by carbs the blood sugar drops less - even though glycogen is used up?

I definitely don’t want glycogen to be so depleted that my body starts breaking down muscle (catabolic), but I do want to improve insulin sensitivity as much as possible.
 
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