How do I calculate LBM (Lean Body Mass)?

(Ashley Haddock) #21

Thank you! I love when you get all science-y. :grinning:

(anonymous271) #22

I have a scale that shows % fat, %water, %muscle, and % bone. Do I use total of bone and muscle to calculate lean body mass, or do I also include %water?

Iā€™ve been using just %muscle and %bone but I wonder if that results in a low number for figuring protein intake.

Thanks!

(David) #23

I have a similar scale. I think you just discount the %fat from your total body weight.

Or, use a formula like ā€¦ http://www.calculator.net/lean-body-mass-calculator.html?ctype=metric

Using the web-link gives me the following result

The Boer Formula Result: 79.8 Kgs
The James Formula Result: 78.5 Kgs
The Hume Formula Result: 73.3 Kgs

The scale says 83.59Kg (117.4Kg weight, 28.8% body fat = 33.81Kg.)

Given that the scale says my muscle mass is a bit low (because Iā€™m soft and cuddly) I would say that the formula are not that far off, but obviously the scale takes more into account.

(anonymous271) #24

Thanks, that was the way I was leaningā€¦

(Casey Freeman) #25

I live in the Woodlands and there is a place that will do a Dexa Scan for $50.

http://www.biometrixlife.com/contact-woodlands.html

(John) #26

Not sure why these seem as far off for me as BMI but they are. Mine says:
The Boer Formula Result: 146.4 lbs
The James Formula Result: 149.7 lbs
The Hume Formula Result: 136.4 lbs

I am 203 so I am 48% fat according to Hume and 35% according to James. My scale says 23%, the visual charts which are not really good but closer to 20% than 25% and the guy at the gym who is all about this stuff guesses 18%.

That is a drastic difference.

Edit: Since I mentioned BMI, mine comes out to 28.3 which means I am borderline obese. I am not. Any more.

(Stickin' with mammoth) #27

My calculator is a pair of jeans from 2001. When I can put one leg in, Iā€™m 50% as lean as I want to be. When I can put both legs in, 80%. When the button fastens and I can still breathe, 100%. Never needs charging.

(eat more) #28

this has been a huge source of frustration for me

such a large spread between different methods/formulas/visuals totally throws off everythingā€¦except carbs lol

bioimpedence (aria, tanita, etc) is stupid at best and just guesses based on a group of test subjects of similar age, weight, heightā€¦just a glorified calculator only worseā€¦i have a friend doing a ā€œfitness challengeā€ and he drank a gallon of water prior to testing to get a higher bf%ā€¦so not even good for ā€œtracking progress even if the actual number is wrongā€

while i love mathā€¦the calculators are also based on ā€œsimilarā€ subjectsā€¦l want my actual numbers

so without access to dexa or possibly hydrostatic (iā€™ve read thereā€™s inaccuracies there too, but who knows) itā€™s all just guessworkā€¦which sucks for my n=1 :joy:

ok now i think iā€™m just whiningā€¦

(John) #29

Its hard to even figure out what protein and calories you need with that kind of fluctuation. I would be dropping weight really fast if I set a 20% deficit based on that lower calc for body fat.

(John) #30

That wonā€™t even work for me, I am almost in my last uniform pants from the military. I got out at 225 with a 34" waist, I am now 203 with about 35" waist. Lots of difference in composition!

(eat more) #31

right!
losing LBM, lowering bmr because youā€™re relying on fat stores that arenā€™t actually there to meet your needs

#32

thatā€™s cheap, in the UK itā€™s 150 and only in London so add travel to that :frowning:

(Stickin' with mammoth) #33

This is the reverse of a hilarious Marine Corps Ball incident from the 90s. Iā€™ve been to three of them (100s of dudes in uniform, drool) so Iā€™ve become privvy to a few behind the scenes facts civilians never learn.

Fact 1: Nobody can take their jacket off at the ball until the Brigadier General does.

Fact 2: If you sit at the Brigadier Generalā€™s table, you are screwed and you must spend the rest of the night getting him as drunk as possible so that jacket comes off.

Fact 3: Brigadier Generalā€™s wives are not known for their fashion sense nor their ability to hold alcohol.

Fact 4: When the Brigadier General finally staggers out of the room with his giggling wife and her skin-tight, size 18, yellow sequin tube dress from 1987, a deafening testosterone cheer erupts in the dance hall, 317 dress blues fly into the air, and you learn just how many of your friends were using Duct tape to hold together a uniform two sizes too small over their college food babies.

(Jamie Hayes) #34

Hey all,
Surely there is an easier way. The main reason people want to determine their LBM is to calculate their protein intake which typically has a range of 1.0 to 1.5 g per kg LBM.
Why not develop a protein range based upon your height? It would be so much simpler and cheaper.

(John) #35

Awesome story! I actually had this task, as soon as I arrived to base I was told I was the youngest Marine on base so I had to get my blues done ASAP because I was part of the ceremony. The oldest had been in I think 8 years before I was born.
We had fun at the ball, but it was the only day we were allowed to wear our dress uniforms in public. Shootin fish in a barrel :smile:

(Stickin' with mammoth) #36

There was a massive ROTC program at my university so all this girl had to do for a date on Friday night was pick the age, weight, and size. *rimshot

(Justin Hayes) #37

These arenā€™t available yet, but if it was any good, iā€™d be interested!
Obviously, costs as much as a few DEXA scans, but you could do it far more often - if it were any goodā€¦

(John) #38

1 to 1.5 is a fairly large range, so I guess worst case I could shoot for 1.25 and I would likely be somewhere in that range in reality.

#39

Personally, Iā€™m fine with the margin of error from my Fitbit Aria scale because it was ā€œclose enoughā€ when compared to a DEXA scan I had a few years ago, but if I had to get more serious on a limited budget, Iā€™d resort to the caliper method since itā€™s a direct measurement of subcutaneous fat in specific regions of the body.

As lamented earlier in this thread, the various equations arenā€™t direct measurements and at least the calipers are cheap and measure something on your own body and clearly take into consideration the differences between muscular and non-muscular individuals at the same bodyweight.

(I want abs... olutely all the bacon) #40

Has anyone used the Omron Fat Loss Monitor for a % body fat reading? What is the accuracy compared to Dexa scans and other tools?
https://www.amazon.com/gp/aw/d/B000FYZMYK/ref=mp_s_a_1_1_a_it?ie=UTF8&qid=1487193458&sr=8-1&keywords=body+fat+measuring+device