How do I calculate LBM (Lean Body Mass)?

(eat more) #41

i love your posts they’re always entertaining :blush:

(Stickin' with mammoth) #42

Well, I can’t afford Prozac, so…

(eat more) #43

it’s “bioimpedence” so i have no faith in its accuracy…but i’m bitter about bioimpedence LOL

(I want abs... olutely all the bacon) #44

It gave me a % body fat that was MUCH lower than the calculations, likely wishful thinking on my part :blush:

(eat more) #45

it can go high or low depending on time of day, activity, hydration, what you’ve eaten, how relaxed you are and believe it or not how tightly you grip the handles.

even if the “current” was actually measuring anything the handheld dealios are only “measuring” from hand to hand…what about my butt?!

it drives me bananas that the “personal trainers” at my gym use this with their clients and don’t have calipers let alone know how to use them!

that’s like me not knowing how to use scissors and i do hair…

my bitterness explained :joy:

(Todd Aaron) #46

I use the Navy method for figuring bodyfat %. More accurate because it uses measurements. more convenient than callipers. Uses your weight, gender, and a few measurements with a tape measure.
Today I am 145.52 lean mass.

I think these formula based results are off because they don’t account for more than average muscle possibly?
The Boer Formula Result: 135.1 lbs
The James Formula Result: 137.5 lbs
The Hume Formula Result: 127.9 lbs

One of the many navy method calculators out there is located here: http://www.linear-software.com/online.html

#47

That somewhat exists in the BMI ranges, in that you can use your height and current weight to figure out the LBM, but it’s not particularly accurate. The reason LBM is more important than height is LBM gives you a better idea of how much protein needs to be replaced in the body every day (a percentage of your lean cells will be damaged every day and need replacement or repair with mostly proteins, though some parts will need certain fats as well). The best height will do is tell you how much skeleton is involved (thickness of bone, density of bone, etc would still be unknown) and maybe an approximation of how much lean tissue would normally be there to support such a skeleton (but, again, then we are in the BMI area for accuracy). That range, by the way, typically accounts for certain other matters like are you actively trying to build muscle/more LBM through work outs and such, along with some degree of individual variance for needs. But, really, you usually don’t want to just shoot for anywhere in that range regardless of what you are doing, so you do want a better accuracy level if possible.

#48

Personal trainer here. Just my observations: Calipers are tricky to use. It takes lots of practice to be accurate with them. Some people are resistant (self-conscious) to having their fat pinched. Bio-impedance, while not as accurate as a DEXA scan, takes out human error. Even body measurements with a tape measure is tricky. 1/2 inch higher or lower on an arm or thigh can make a lot of difference and be demoralizing if a client has been diligent and doesn’t see the results they want to see.

(eat more) #49

i completely disagree…
bioimpedence can easily be manipulated by the human

it can also report a gain in body fat when you’ve actually lost

it’s just an algorithm that guesses based on data entered

so human and device error…

i personally would rather guess or not know at all than the mind game that is bioimpedence readings…way more disheartening than having your fat pinched

it’s even less useful than using a scale to measure your fat or fitness levels

(David) #50

Are you saying that my fancy scales that measure body fat, hydration, muscle, weight, and all that stuff are just doing maths?

(eat more) #51

basically…

bioimpedence is measuring the speed at which a current travels from point A to point B

muscle has more water than fat, water is a conduit, faster circuit with more muscle BUT electricity always follows the path of least resistance so it may not even be measuring fat or muscle…

as i understand it the device takes the “speed” result and then uses maths…based on study groups of similar height/weight/age subjects…
i put BIA in the same trash can as BMI

(Beth) #52

I agree completely, @Todd_A (about not accounting for more than average muscle). Having been athletic all of my life, I am certain that my weight is a higher number than most of my same-height and age companions. This seems really wacky to me. I don’t track my food, I don’t pay attention to it much, so I’m not sure why I care. I eat keto to keep my sweet tooth under control and for better general health (sleep is a biggie). Mostly shooting from the hip seems to work for me so far, so I shouldn’t really care about these numbers and yet here I am!

(Louise ) #53

My Fitbit Aria was off by a massive 12% :rage:

(Louise ) #54

Most definitely - it uses an algorithm for male and female - and had a huge variation for me by 12%! I ended up having a DEXA scan and had the Aria say I was 36% and the DEXA revealed I was 24%

(Jennifer) #55

Richard’s calc and most bioimpedance calculations work off standard body types. If you have a normal build it works great. If you are very muscular or big boned, it isn’t close.

My scale lets me pick male/female and there are two settings - regular and athletic. The normal puts me at 42.8% and the athletic puts me at 37.8%. That would be an LBM of 115 or 125.

The Boer Formula Result: 110.8 lbs
The James Formula Result: 109.1 lbs
The Hume Formula Result: 111.2 lbs

I think I’m closer to the athletic. Trying to schedule a DEXA scan in the near future.

(Boston_guy) #56

The Skulpt is good and cheap for repeated measurements. I take a couple measurements, average them together to reduce measurement error. Would love to do a Dexa, but the time and expense are hard to justify…

(Jennifer) #57

I got my numbers and my scale is pretty close. LBM is 115.

(Pete A) #58

This month I’m buying this! Have you been using it @Becky ?

(I want abs... olutely all the bacon) #59

I didn’t buy it, I’m interested in how it works for you.