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Question About Gluconeogenesis


Hello All
First of all, SORRY for my bad English. Ä° hope i can explain my questions.

1)Think a person in low carb ("low" not "no") high protein diet.
When liver and muscle glycogen is deplated or too low during weight training and cardio at last, the body will directly start gluconeogenesis ? or if im wrong what is the process about fat burning.

2)What is the ratio (%) of protein/fat that is converted to glucose in gluconeogenesis?



Depends on what you mean by "directly," I suppose, but it will start automatically.

This would depend on the amount of gluconeogenic precursors available and your (dun dun dun) genetics. Precursors for gluconeogenesis include the glycerol backbone of triglycerides (typically not the fatty acids, themselves), amino acids (all but lysine and leucine), pyruvate, lactate (which makes your muscles burn) and, to a lesser (possibly insignificant) extent, branched-chain fatty acids and those with an odd (odd as in not cleanly divisible by two, not odd as in being unusual) number of carbons.

The amount of gluconeogenic precursors available is a reflection of your diet (e.g., more protein intake equals more protein turnover) and activity (e.g., prolonged low-intensity exercise increases fat mobilization and, subsequently, glycerol availability, whereas brief, high-intensity exercise increases lactate production which skews both ratios due to its conversion to glucose via the Cori cycle).


Thanks for your attention and answers. :slightly_smiling:
In my 1st question, I mean, Example lets say:

Daily Pro. intake: 2 gr/kg
Carb.Intake: 3 gr/kg
Fat. intake: 0,8gr/kg
I did 3 set circuit training and after that begin cardio (30 min.) with %65 heart rate. In this scenario my body will start gluconeogenesis at first right ?


you are an interesting poster anonym. what science degree do you have?


I don't quite know what you mean by "at first"... but your body will start gluconeogenesis upon depletion of liver glycogen -- that's honestly the best answer I am comfortable giving.

If and when that occurs will depend upon numerous variables not listed in your example: the types of exercises in your circuit, the number of exercises per circuit, the number of sets per exercise, the number of repetitions per set, how hard you pushed yourself during your circuits, your energy level during the workout, how much food you ate leading up to the workout, the distribution of nutrients in each meal, the activities you did prior to hitting the gym, if you are taking any "supplements", your general metabolism, etc.

All these things will affect how much glycogen your body has stored and will be needing to use. Unfortunately, I can't do much better than my first sentence without writing a long-ass post that I don't have much time for at the moment.


Thanks, man.

My education was, for the most part, in clinical microbiology.