BMI, lean body mass, and goal weights

[Vex 0]

I am 5'2". I have a large frame. I don't mean that in the way that people say that fat girls are "big-boned," I mean I literally have a larger and more musclular frame than most girls, period. I have thick joints, muscular calves and thighs, biceps and shoulders, etc. I always have; I (unfortunately) take after my dad's stocky, athletic side of the family.

I was weighed at the clinic on the day before my surgery, on of those scales with electrical impedance that measures your body fat percentage, so the nutritionist gave me my lean body mass: 131 lbs. Lean body mass is, supposedly, muscle, bone, and organs-- any tissue that is not fat, basically. This is not unusual for me; I've been tested several times at different places (the gym, a boot camp program I did recently, I have my own body fat % scale, at the school clinic when I was in college) and that number is just about the same that I always get (upper 120's to low 130's would be the range, I'd say).

Which is, of course, really funny because at my height and age (28), 131 is nearing the upper edge of the "healthy" weight range (104 - 137). A woman with the healthy, recommended percentage body fat percentage of 20%, with 131 lbs of lean body mass, would actually weigh 164 pounds total!

Which is actually a BMI of 30, which puts that person at obese. Not overweight, obese.

I am a runner, but a casual one. The longest race I've run is a 10-miler, most weeks I bang out 10 - 15 easy miles. I don't lift weights, but I do jump around from activity to activity, such as spending a couple months doing a Boot Camp in my neighborhood, to doing the gym routine, to just doing the running thing and a few at-home calisthenics. I am in no way a serious athlete.

So here's my question. Am I going to lose lean body mass as I lose body fat? I have no intentions of limiting my exercise routine; in fact I hope to get more serious about my athletic endeavors as my body works better. The nutritionist indicated that losing 50 - 60 lbs would be ideal for me, putting me at 161 - 171. But that is really, really, really big for a 5'2" girl.

Laughably, my goal when I used to go to Weight Watchers (sporadically for years) was 129. Hahahaha, yeah right!

Is my goal of 149 lbs reasonable? Am I analyzing this problem properly?

[JulieNYC 4]

Vex,

I went through what you're going through. I think it's normal to analyze it, and I think your logic is good, but I would also encourage you to not worry about it so much because if you get to 160 and are happy with your body, great! If you get to 150 or 140 or wherever and are happy, great! You'll know goal when you get there and you can re-set goal whenever you want to.

I set my first goal at 170. When I got to about 190, I knew 170 wouldn't be enough, but I still thought the 130s were ridiculous for my frame. So, I set another goal of 159. Now that I'm below that, the 130s doesn't seem so unreasonable, so I'm aiming for 136 (the highest normal weight by the charts I use). But, if my body stops short of that, that's ok too. I'll let my body decide where goal is because I don't want to fight to stay at someone else's arbitrary number, you know?

[WASaBubbleButt 41]

Yes, you will lose some muscle during massive weight loss. The idea is to limit the amount of muscle you lose. You do that by doing what you are doing now, keep up the exercise (especially weight resistance) and keeping your Protein up.

Don't worry about a final goal now. Focus on a realistic goal and when you get down to where you want to be, you'll know.

[Vex 0]

Thanks Julie, thanks, uh... UnBubble!

So I infer from your goal, Julie, that you are also pretty short?

[Jachut 487]

Yes, you will lose lean body mass as you lose fat. Your job is to minimise it but at the end of your journey, you will not have 131lb of lean body mass. YOu cannot work out your goal weight that way.

You may always be bigger framed meaning you may always have more lean body mass than the next person. That gives you permission to weigh more than them! But you just have to see how you go as you go along.

I'm the opposite. I'm 5ft 10, 168lb, and a BMI of 24. I'm normal, healthy weight. I'm still too fat - my body fat percentage is 30%. Despite being a runner and doing strenght training 3 x a week all the way through. My hands are skinny, my wrists are bony, my shoulders jut and my collarbones stick out but on the lower half of my body is too much fat! I need to weigh much lower in my healthy weight range and have a much lower BMI becuase I do not ahve a frame that is muscular, has big bones or lots of lean mass.

I have weighed probably as litte as 154lb in my adult life at this height and THAT was not skinny for me either. I still had thighs, a belly roll at that weight. I need to be in the 140's really to be what you'd call slender, not sure I could be bothered losing that much though, I dont think I'd be able to maintain it.