Thread: bf% - what is the associated LBM

It's immpossible to tell how much of it is bone and organs. Don't worry about the different rate of burning calories, you're over analyzing it.

might be able to tell how much is bone and organs if you find someone your exact height and body style that is anorexic and has about 10 lbs of muscle total on them..... so search for that body double with the disorder and youve got your answer, either that or search medical books for every organ's normal size and weight (sure its been researched before), and then get a bone density test etc etc. lol but why worry about it, just get your bodyfat as accurate as possible for now, and whne you start gaining muscle, test again and you can see how much you gain/lose with muscle and fat.

in bf% and LBM calculations, it is assumed that

body = fat + muscle ?

what about the bones and internal organs?

Ok -
Body = fat + LEAN MASS.

Lean mass = Tissues, muscles, organs, blood etc etc.

[qute]for a 200lbs person, 15%bf, normal calculations show 30 pounds of fat and 170 pounds LBM. I guess the bf% measuring devices (calipers) give an accurate number for the pounds of fat?[/quote]
Not really - they give you a rough guide but they don't give you an accurate measure of visceral BF... Only sub-cut body fat (which, yes, has a high correlation with BF% in MOST people, but not all people).

How much of it is actually muscle? and I imagine bones and internal organs consume energy at different rates than muscle...

There are rough formula you can use to tell what different organs have (eg: The average male of 75kg, who has a BF% of 15%, has a liver that is ~1-1.6kg)... But the amount of muscle an individual will have is highly variable.

Different organs use energy at different rates too....

I think I have a journal article somewhere... Yep - there are some tables etc here that give you formula and resting metabolic rates for some organs :Resting energy expenditure-fat-free mass relationship: new insights provided by body composition modeling.

I was just wondering, because most of the diet calculations are based on LBM (which I understood to be muscle until now, my mistake).

e.g. 1-2g /pound of lbm protein, calories <10x LBM enter starvation mode etc...

So the bone mass may be a significant amount, but it's probably already taken into account in the above mentioned calculations