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How Much of LBM is Skeletal Muscle?


So I know my LBM and I want to know how much of it is sceletal muscle tissue because I want to find out how much my glycogen stores really are, because I seriously doubt that they are only around 500g.

So want to eventually figure out is how much glycogen I can really store because I tend to diet low carb and I dont want to lose too much muscle while doing it.

So far the difference between fully carbed up and hardly any carbs seems to be 5-7kg which is significantly more than the 1,5-2 kg it should be if I only stored 500g.

Any ideas?


if your trying to prevent catabolism...I would be more worried about depleting liver glycogen than muscle glycogen...

your brain relies on liver glycogen as it's main source of energy...if it gets depleted, your body will start breaking down protein....

most people store anywhere from 80-100g in their liver....your brain will deplete that entire amount in less than 24 hrs(most likely 14-16 hrs)...


I would just follow the guidelines in McDonald's Ultimate Diet 2.0 or The Ketogenic Diet for carb-up (I think they're around 15-16g/kg of carbs). Also, don't confuse muscle glycogen with generalized water retention.


I want to know how much muscle I really lose or whether I am just losing glycogen and water.


I understand what you are saying about the extra weight differential between 1.5-2 and 5-7 kg. At first I was thinking you may be full of shit when fully carbed up (literally) but I dont see anybody holding that much shit in their intestines. Supercompensation from going low carb to really high carb may make you hold significantly more water and glycogen but I don't see it making that big of a difference.
Personally I wouldn't worry about it. Carb up once a week while on the diet and measure your weight the morning after so you can get a constant reading week after week.


This thread makes my head spin.


You're talking about body composition, as if it was the same in every human being. The only solution is to play with your carb intake and loading period.

The last cut I did this experiment, and felt good taking like 400 grams of carbs for 3 days instead of the 600-700 in one day. I had more definition on my tricep and the workouts felt really good again. More would've been just pure bloat IMO.


DEXA scan.



you will break down protein if liver glycogen is depleted....that is fact...

your body can't convert muscle glycogen to glucose to fuel the brain...

If you are ingesting a high protein intake, your body will use those availible aminos over muscle tissue...But, during sleep, you are at risk for muscle loss...


Sorry man not to jack the thread but a question on the same topic, how much does the skeleton actually weight? Im a 6'5 individual, if you were to strip away all my muscle fat etc, how much would my skeleton weight?


DEXA scan


(google bone density)


How does this, in any way, answer the question of "how much glycogen is lost while in ketosis?"?


he didn't ask me that(never said he was doing keto diet either)...he asked me specifically how much muscle he would lose if he was in a depleted state...

i don't know exactly how much muscle he will lose...so, i explained how someone could lose muscle on a very low carb diet...so, he could better understand how to prevent that...

If you are ketosis, you will use ketones of course...but, he never said he was doing a keto diet...


What I specifically asked was how I could possibly find out how much of my LBM is muscle that can actual hold glycogen so that I could establish a baseline of carb depleted LBM and know when I fall below it.

Cause 500g of glycogen seems a bit low for me.


Only post needed here to answer OP's inquiry.


I'm not going to continue the discussion...

i doubt you will be able to use the info you are trying to obtain, so it is pointless...

if you are truly interested, read lyle mcdonald's ketogenic diet book...


He didnt ask YOU anything.

And I mentioned ketosis because it removes a variable.

Your posts dont even make sense in this thread. And the only reason Im replying is because I am genuinely curious about what the answer may be, even if it is different for different people.


What he said.

DEXA scan is awesome!


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I see your point...only reason i brought up my points is he is worried about catabolism, and i explained that he would have protein losses before he even depleted his muscle glycogen....

i'll try to answer your question though...

search google for "Training on the Cyclical Ketogenic Diet: Effects of Cyclical Ketogenic Diets on Exercise Performance"...a lot of the info i'm using comes from there....

studies done on trainees using 70% of their max...found glycogen depletion per set at 7.5 mmol/kg/set...this was tested on legs, so i'm not certain how comparable it is...but, we will use it...

a normal human has 100 mmol/kg of glycogen concentration in each major muscle group....someone in a keto diet has aprox 70 mmol/kg availible....if you carb up to super compensate, you could hold maybe 120-130 possibly 150 depending on how long you carb up...


this text has similar figures....

so, you could figure out how fast you will deplete glycogen based on that...

to carb up, LM's reccomendation is 10g/kg of LBM for the first 24 hrs to return to normal levels...then 5g/kg of LBM for the next 24hrs to achieve supercompensation...