Weight Loss Support - Lean Body Mass and Goal Weights




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lunarsongbird
02-06-2013, 01:03 PM
Hello Everyone!

I have been thinking about goal weights this morning. I have always picked my goal weights based on medical charts. I'd like to be in the middle of the average BMI. I want to be in the middle of the fat percentage charts. However- it occurred to me today that maybe I don't fit into those charts.

Here is a bit of math I was doing this morning:
Initial body fat: 242 pounds x 47.3% body fat = 114 pounds body fat
Lean body mass: 242 pounds total – 114 pounds fat = 128 pounds lean body mass (bones, organs,…)

My lean body mass is 128 pounds. Am I ACTUALLY big boned? LOL. And I wanted to get to 135? That math doesn't seem healthy or even plausible, right? (I'm really really bad at math...seriously, I need a little help. LOL).

In college, I got down to 149, but perhaps my muscle mass was a bit different then.

Can someone help me do the math to figure out what a really healthy weight would be for me? :?:

Also- does anyone else know their lean body mass? And have you taken it into consideration when picking a goal weight?


nelie
02-06-2013, 01:08 PM
At my highest weight, my lean body mass was something like 180 lbs :) Trust me, when I hit 200 lbs, I wasn't all lean body mass.

Basically, lean body mass is everything but fat so that includes the tissues that support your higher weight. As you lose weight, you'll lose lean body mass. This includes some muscle (as your smaller body won't require as much to carry you around) and tissues (as your smaller body won't require as many tissues and associated water to support you).

So I'd really not worry about it until you lose more weight and see where you are at.

LockItUp
02-06-2013, 01:17 PM
Lean body mass will decreas as you lose, no way around that! Not just talking muscle mass, though that is probable at least a little bit, but other things lessen as well -- skin, I've even read things like ligaments, cartilage, and tendons (though I don't have a source so take it for what it's worth, my possibly bad memory) and so on and so forth.

My math:

Starting 220 (well, when I was brave enough to calculate) pounds, 42% body fat which is 92 lbs of fat, and 128 pounds of LBM.

At my current 139 pounds I am most definitely NOT 128 pounds of LBM. My body fat is around 23-25%, let's go with the highest one just for fun: that's 34 pounds of fat, 105 pounds of LBM.

Now, even taking into account that my body fat calculator thingie isn't accurate to reality, it's at the very least accurate to itself within a percent or two, so the numbers would still work out the same, and as you can see I'm down many pounds of LBM.

Hope that helped instead of making it worse lol.


newleaf123
02-06-2013, 01:17 PM
I've gone through all those machinations, too (yes, I got my lean body mass from the gym when they did all the measurement and test stuff), but have set it aside -- both for the reasons that nelie articulates above, and also because I imagine that there is some measurement error in there, too.

I'm very quantitative by nature, which is exactly why I don't count calories or anything else -- it makes me batty! And this fat % stuff falls into the same boat (for me personally).

I do plan to go back and redo all the measurement and test stuff at the gym, exactly 1 year after I did it the first time; it will be interesting to see how everything changes. So I guess that's my advice to you -- good to know for now, measure it again in a year and see how it changes. Don't let it drive you batty.

TripSwitch
02-06-2013, 03:31 PM
Here's one thing I've come to realize lately... I can do all the math in the world and come up with a lot of things that look good on paper... but for some reason it rarely translates to the real world all that well... for me at least...

But as far as picking a "number" if you weighed 149lbs before and that was manageable for you and you think it can be again... then I could see setting your goal somewhere in that neighborhood... and then once you get there you can see how you feel...

chubbybunny29
02-06-2013, 05:10 PM
Women should be between 18 and 25% body fat. So if your Lean Body Mass is 128lbs, your healthy weight range is between 151 and 160.

I found out about this a few years ago when I found out my lean body mass was much higher than I thought and I should be between 167 and 184. I still have a LOT to lose but knowing that my healthy weight was higher than I thought was a nice thing!

Robin41
02-06-2013, 05:38 PM
I don't want to be the Debbie Downer, and I spent a good bit of time running all these calculations myself at one time, but until you get down a good deal of weight, there really isn't any legitimate way to know what your ultimate weight and lean body mass will be.

It might make perfect sense for somebody who has to lose twenty pounds, but when you're talking about 100+, your body will be so vastly different when you get there that it's like comparing two completely different people. Every method in the known universe called me large framed and yet when the weight actually came off, there was a medium frame hiding in there! Who knew?? Certainly not me, and not the trainer at the gym who did my initial body mass calculations and suggested I would end up in the 185 range.

You'll know when you've lost enough weight, and you'll know when you've got yourself into pretty decent shape. You get a sense of being lean and fit that doesn't require a calculation to verify it. You just feel good.

Enjoy the process and don't think too much!

LockItUp
02-06-2013, 05:38 PM
@chubbybunny - Just don't forget to take into account that your lean body mass WILL go down as you lose weight, there's no way around it!

berryblondeboys
02-06-2013, 05:44 PM
Women should be between 18 and 25% body fat. So if your Lean Body Mass is 128lbs, your healthy weight range is between 151 and 160.

I found out about this a few years ago when I found out my lean body mass was much higher than I thought and I should be between 167 and 184. I still have a LOT to lose but knowing that my healthy weight was higher than I thought was a nice thing!

Where do you get that? the 18-25% body fat is where women should be? Every chart I have seen says that 25% and under is "fit" but under 30% is acceptable.

lunarsongbird
02-06-2013, 05:46 PM
I don't want to be the Debbie Downer, and I spent a good bit of time running all these calculations myself at one time, but until you get down a good deal of weight, there really isn't any legitimate way to know what your ultimate weight and lean body mass will be.


Robin, You aren't being a debbie downer at all! This is exactly what I wanted to hear.

I appreciate everyone's responses! I had no idea that my lean body mass could change and I'm thrilled to hear it! I was a bit disappointed to hear that my original goal was possibly entirely unfeasible. Now it sounds like it might be a reality based on what happens in the future as my body is changing! Hooray!!

lunarsongbird
02-06-2013, 05:47 PM
http://4.bp.blogspot.com/-MnKm8q4DrBo/Te-uyl8O-rI/AAAAAAAAAKI/nqepVjMFaZQ/s1600/Body+fat+percentage+Calculator+your+fitness+partne r.jpg

freelancemomma
02-06-2013, 06:04 PM
Here is a bit of math I was doing this morning:
Initial body fat: 242 pounds x 47.3% body fat = 114 pounds body fat
Lean body mass: 242 pounds total 114 pounds fat = 128 pounds lean body mass (bones, organs,)

My lean body mass is 128 pounds. Am I ACTUALLY big boned? LOL. And I wanted to get to 135? That math doesn't seem healthy or even plausible, right? (I'm really really bad at math...seriously, I need a little help. LOL).


Your math is fine. I think the missing bit of information is that when you lose weight, you don't just lose fat, you also lose some muscle (part of your lean body mass). So if you were to get down to 135, your lean body mass wouldn't be 128 anymore -- it might be 100 or 110 -- so you wouldn't be skin and bones. That said, maybe you do have a large frame and would be healthiest at a somewhat higher weight.

Freelance
www.englishgrammargripe.com

200poundquest
02-07-2013, 04:03 AM
I have a lot of weight to lose and I've never been not overweight, so I set my long term goal based on how much I think I would need to have lost at my lowest weight to be "normal" for my body type, frame, height etc.

However, I fully intend to re-evaluate that when I get closer to that number, because it is just too hard to really know exactly where you will be comfortable when you have that much weight to lose.

I focus more on my short term goals than on the ultimate number.

I love stats and numbers too, but weight loss just isn't an exact science and there's a lot of room for error, so I don't think locking yourself into one perfect goal weight is particularly productive.

sontaikle
02-07-2013, 08:30 AM
Robin, You aren't being a debbie downer at all! This is exactly what I wanted to hear.

I appreciate everyone's responses! I had no idea that my lean body mass could change and I'm thrilled to hear it! I was a bit disappointed to hear that my original goal was possibly entirely unfeasible. Now it sounds like it might be a reality based on what happens in the future as my body is changing! Hooray!!

Just as nelie said further up the thread, you can't keep all of your lean body mass if you're losing a significant amount of weight :) Our bodies build up a lot of muscle carrying us around! We just won't need all of it when we're smaller.

When I was 182 pounds, calculators put my lean body mass at around 106lbs. I likely had even more when I was over 200lbs and when plugging in measurements I remember I get weights that are close to what I weigh now.

Now, at 112-113 the calculators put my lean at 94lbs. So I "lost" 14lbs of lean, but I probably didn't need all of that at this smaller weight. I lifted on the way down, ate healthfully, etc. so I did keep a lot of lean and end up with a lower bf% but even then I couldn't keep all of it :)

And of course the only way to REALLY know how much body fat and lean we all have is the good ole dunk test. So the calculators just really give us a frame of reference :)

lunarsongbird
02-07-2013, 11:35 AM
Eeeep! The dunk test! LOL. I wonder if that comes to Colorado. I did it in a mobile unit in California and I felt like I was drowning! LOL. Accurate though!