Help me understand my bodycomp results

ChickenKillerPuppy

Hi all,

As part of my annual wellness exam, my doctor does an "InBody" body comp report and I know a lot of people on these forums know a lot about this stuff. I know you are all a bunch of internet strangers and I promise I am not going to rely on anything anyone posts, and I will ask my doctor any "real" questions I have, but I was just curious for those of you who are into this stuff if you had any thoughts on my results which I will post below.

The only thing I really understand is body fat percentage and BMI, so interested in the significance of some of the other figures. I did a little googling but couldn't find out much. If you have any insight, please share! (and I will take it all with a grain of salt because I know these are just internet forums).

AGE: 49
HEIGHT: 5'4"
WEIGHT: 127
BMI: 21.8
Total Body Water: (lbs): 71.4
Dry Lean Mass (lbs): 26
Body Fat Mass (lbs): 29.3
Percent Body Fat: 23%
Skeletal Muscle Mass (lbs): 53.1*
Body Fat Mass (lbs) 29.3*:
* the little bar graph on the report shows the SMM being longer than the BFM and my doctor said that was good, that it means I am more muscle than fat, but I don't really know if I correctly understood
SEGMENTAL LEAN ANALYSIS:
Left Arm: 4.87lbs; 120.2%
Right Arm: 4.87lbs; 124.7%
Left Leg: 13.47lbs; 90.8%
Right Leg: 13.47%; 90.4%
Trunk: 42.4lbs; 96.7%

Most interesting to me perhaps was that my Basal Metabolic Rate was (at least according to this report) : 1327 calories. That is much higher than I would have thought!

cwolfman13

I don't know that there's really much significance to the other figures relative to BMI and BF%. Why did you think your BMR would be much lower? 1300-1400 is pretty on par for average female BMR.

sijomial

BMI and BMR aren't direct results from the scan - simply using your height/weight and height/weight/age/gender stats respectively.
Just like you can on MyFitnessPal and a load of other online calculators.

But it might be taking your estimated fairly low bodyfat percentage numbers into account to give a higher BMR number than other calculations which might assume a higher BF% for your demographic.
Trouble is a BMR estimate on its own isn't really of any practical use!

If you wanted a RMR test that would be done by breath analysis and not by putting an electrical current through you.

Although the InBody is a high end device of its type they all need care using under consistent hydration conditions and ideally a whole series of regular scans to see a trend and also highlight any freaky / inconsistent results. Once a year I wouldn't put too much significance on the numbers to be honest - interesting but not that reliable.

Xellercin

What did your doctor say was the purpose of this test? What actionable data did it provide? What interpretation did they give?

Tests aren't valuable in and of themselves, they need to come with interpretations and recommendations to be worth anything in a clinical setting.

I'm a little confused as to why your doctor ordered this test for you.

goal06082021

ChickenKillerPuppy wrote: »

AGE: 49
HEIGHT: 5'4"
WEIGHT: 127
BMI: 21.8
Total Body Water: (lbs): 71.4
Dry Lean Mass (lbs): 26
Body Fat Mass (lbs): 29.3
Percent Body Fat: 23%
Skeletal Muscle Mass (lbs): 53.1*
Body Fat Mass (lbs) 29.3*:
* the little bar graph on the report shows the SMM being longer than the BFM and my doctor said that was good, that it means I am more muscle than fat, but I don't really know if I correctly understood
SEGMENTAL LEAN ANALYSIS:
Left Arm: 4.87lbs; 120.2%
Right Arm: 4.87lbs; 124.7%
Left Leg: 13.47lbs; 90.8%
Right Leg: 13.47%; 90.4%
Trunk: 42.4lbs; 96.7%

Most interesting to me perhaps was that my Basal Metabolic Rate was (at least according to this report) : 1327 calories. That is much higher than I would have thought!

I'll go ahead and +1 that 1327 is a pretty normal BMR for a woman your size.

So, according to this, your 49-year-old human body stands 5 feet, 4 inches tall and weighs 127 pounds. Converting those figures to meters and kilograms and then doing some more math on them gives a BMI of 21.8 kg/m^2. Great, that's well within the range defined as "normal." Everything below the BMI line is basically describing what we would see if we could break your human body down into its component parts and weigh those parts.

Total Body Water: You might remember from middle school biology that the human body is mostly water; of your 127 lbs, about 71 of those are water, or about 56%, which is pretty average.

Body Fat Mass is also pretty straightforward; of your 127lbs, about 29 of those are fat, working out to about 23%. Also average.

Dry Lean Mass is a little more disturbing to think about, and also not really a practical measure but it's basically what's left after accounting for your water and fat contents. So, imagine we've dissected your 127-lb human body, and taken your ~29 lbs of fat and put them in a pile off to the side. What's left after that is called your "lean mass" - that's bones, muscles, skin, internal organs, and all your various human fluids - blood, pee, tears, cerebrospinal fluid, all that good stuff. (Simple math tells us that "lean mass" pile would weigh about 97 lbs.) If we put all of that into a big ol' dehydrator and got rid of all ~71lbs of water, the stuff that remains would weigh 26 lbs all together.

You might also remember from high school biology that there's basically 2 kinds of muscle: skeletal muscle, so called because those muscles are attached to your skeleton and make it move (also called striated because they're made of long fibers that give the muscle a "stripy" appearance), and smooth muscle, which is what your organs are made of. If we go back to our imaginary dissection, before jamming all your non-fat tissues into that dehydrator, if we separated out your muscles from your organs and bones and stuff and weighed those, they would come in around 51 lbs (including their water content). 51lbs is more than 29lbs, and yes, it's generally good to have more muscle than fat in your body.

I'm not as sure about the "segmental lean analysis," but I'm interpreting that to mean that your arms have less fat on them than your legs - maybe ask the doc again to walk you through those figures.

ChickenKillerPuppy

Thanks everyone! This was just a "perk" that came along with my annual physical at my doctor's practice, it wasn't ordered special for me. I appreciate everyone's insight. My research shows my BMR is a little higher than average for a woman my height and age, which I hope is due to the muscle I have worked so hard to develop! In the past I had always been a cardio person but have been reading so much about the benefit of building muscle instead and I have been doing barre classes (building muscle using very small weights and doing many small repetitions in the various moves) over the past couple of years and I can tell how much stronger I am.

It almost makes me want to cry to think how far I have come from being that fat girl who was afraid to step on a scale. I was so excited that this was part of my physical and it is really interesting to see the results.

PAV8888

You're a lean mean fighting machine.

Your BMR may be taking into account your relatively low fat percentage (ergo higher lean mass) and giving you a slightly higher number.

Remember that BMR means not much I unless the doctors have to feed you while you're in a comma. Your TDEE (usually estimated by multiplying BMR by an activity factor) determines what you spend (and can take in) as calories to maintain weight.

Your tdee is directly observable though logging of intake and long term weight trend...

And, as should be obvious based on results; well done!!!👍