Weight loss vs fat loss vs muscle loss (question)

3foldchord

I read a few spit were people mentioned how many pound FAT they loss ( not total weight loss). I figure it has something to do with calculating total weight loss and fat percentage loss...being slightly math challenged, I asked my 18 yr old if he could calculate that for me. I gave him my numbers. I had no idea what formula to use, but hoped he could figure it out.

I started at 135# and 25% body fat

I am now 134# and 23% body fat

He said something's not right because I lost 3 pounds bodyfat, but only 1 pound on the scale ( 1.2# specifically, but I rounded for math ease)

I am eating at a deficit, and everything I read seems to I dictate I won't gain muscle, except the newbie gain. Nut I figured that was really a strength gain, not a muscle mass gain.....

So, what's going on? Is Connor's math off? Is there a specific formula for this?

( my goal is "lose BF% and keep muscle", so I guess I did ...and I am not opposed to gaining muscle, it's just not something I am trying right now)

stumblinthrulife

Remember that lean mass includes everything that isn't fat. That includes skeleton, organs, waste material and water.

Also remember that any 'measure' of body fat is an estimate. Unless you get in a dunk tank, or have a dexa scan, take it with a pinch of salt.

So there are a few factors, and my guess is what you are seeing is a combination of them -

1. Newbie gains. If you've only dropped one pound, though, presumably the time frame is short and these would be miniscule.
2. Water and waste weight. If anyone ever told you you're full of *kitten*, for once they might be right.
3. Measurement error. Whether tape measure or calipers, there will always be measurement error. To make a jump like this, all you have to do is measure at the high end of this error the first time, then at the low end the next time.

To minimize 'false readings' you can -

Always measure at the same time of day. My preference is in the morning, without having drank anything, and after visiting the bathroom.

Measure twice. If the readings are within 5% of each other, average them and that's your reading. If they aren't, repeat both readings until you get two that are within 5%.

3foldchord

To minimize 'false readings' you can -

Always measure at the same time of day. My preference is in the morning, without having drank anything, and after visiting the bathroom.

Measure twice. If the readings are within 5% of each other, average them and that's your reading. If they aren't, repeat both readings until you get two that are within 5%.

I understand measurements will be off, it just seemed a bit more of descrepency than I thought, condiering it was s small amount to ork witth.

I mesured in the morning {after I wasn't quite as 'full of it'- like last time I measured}, took 2-3 measuremments in as close to the exact same spots as I could (used thee average)- so hopefully I am getting decent measurements. and it's not a big deal, a loss is a loss and it's a good thing! Just wanted to make sure I was figruing fat pounds ost correctly.
25% of 135# is about 33.5# (I forget the exact number I got)
and 23% of 134# is 30.5#

so about 3 # of fat loss using that method.

right? (not accounting for mmeasurement errors obviuosly, just wondered if I was figuring the math correctly)

Sarauk2sf

Tagging

AnvilHead

(Hope Sara and SS don't mind me jumping in here....)

A 2% discrepancy in BF% is well inside the margin of error for any commonly used measurement methodology (except direct measurement via autopsy, which is a bit impractical). Best suggestion is to track measurements over time and watch the overall trend - as long as BF% is trending downward, you're on the right track.

Aside from the possibility of newbie gains, your muscles retain glycogen/water for a while after starting a workout program - it's part of the body's adaptation to the new stress being placed upon it. Water/glycogen is part of LBM, since LBM = anything that isn't fat. So combine the possibility of newbie gains with the possibility of water balance fluctuations and it's easy for measurements to look screwy, especially in the short term. Throw in possible female hormonal fluctuations tied to TOM and it complicates the scenario even further.

Sarauk2sf

^^yep.

Average glycogen and water retention in muscles is about 4lb. LBM is everything except fat, so it includes fluid. This is a common mistake when people say they gained muscle on a deficit. They usually have gained LBM but not muscle. Plus, as has been mentioned, the inherent inaccuracies of the devices.

3foldchord

I know there is a margin of error. I know I don't gain muscle on a deficit. I just wondered if my math formula was correct for finding fat pounds lost. I know there is error, but it'd be silly to never track to figure things out for weight loss fitness because there is error in measurement.

Sarauk2sf

No error. We are just explaining why it may make sense.

AnvilHead

The calculations look pretty right on. Multiply your weight x (100 - BF%) and it will give you lbs. of LBM:

135 x .75 (100-25) = 101.25 lbs. LBM

134 x .77 (100-23) = 103.18 lbs. LBM, for a gain of 1.93 lbs. LBM.


Multiplying weight x BF% will give you pounds of fat mass:

135 x .25 = 33.75 lbs. fat mass

134 x .23 = 30.83 lbs. fat mass, for a loss of 2.92 lbs. fat mass.

3foldchord

The calculations look pretty right on. Multiply your weight x (100 - BF%) and it will give you lbs. of LBM:

135 x .75 (100-25) = 101.25 lbs. LBM

134 x .77 (100-23) = 103.18 lbs. LBM, for a gain of 1.93 lbs. LBM.
.

THANKS for the LBM method!

JeffseekingV

^^yep.

Average glycogen and water retention in muscles is about 4lb. LBM is everything except fat, so it includes fluid. This is a common mistake when people say they gained muscle on a deficit. They usually have gained LBM but not muscle. Plus, as has been mentioned, the inherent inaccuracies of the devices.

What would the difference inbetween LBM and muscle be? Aren't they the same?

AnvilHead

^^yep.

Average glycogen and water retention in muscles is about 4lb. LBM is everything except fat, so it includes fluid. This is a common mistake when people say they gained muscle on a deficit. They usually have gained LBM but not muscle. Plus, as has been mentioned, the inherent inaccuracies of the devices.

What would the difference inbetween LBM and muscle be? Aren't they the same?

LBM includes muscle tissue, bone mass, bodily fluids, connective tissue (tendons/ligaments), etc. - basically, everything/anything that isn't fat.

JeffseekingV

On a calorie deficit, how would one gain that? She said LBM, I think that excludes fluids right?

AnvilHead

On a calorie deficit, how would one gain that? She said LBM, I think that excludes fluids right?

From Sara's post above:

...LBM is everything except fat, so it includes fluid. This is a common mistake when people say they gained muscle on a deficit. They usually have gained LBM but not muscle

You retain water/glycogen in your muscles, which increases LBM - but it doesn't mean you've gained muscle. No, you're not going to see significant gains of bone mass or connective tissue, but water balance certainly fluctuates (Sara mentioned 4 lbs. above, which can induce a pretty significant error into LBM calculations).

JeffseekingV

Does this count for an experienced lifter?

Sarauk2sf

Does this count for an experienced lifter?

If you are an experienced lifter, you should already have the glycogen/water in your muscles, so should not see an increase due to that.

Sarauk2sf

Locking in order to keep track of active threads. Feel free to PM either myself or SideSteel, including a link to this thread, if you wish to add any comments or questions, and we will unlock so you can do so.