Maintaining Lean Mass

BarbellCowgirl

I'm more of a lurker on this forum, but I've been doing EM2WL for 18 months. I've lost 37lbs and 4 pants sizes without ever starving myself.
Anyway, I've read through all the info I can find, but I was hoping some of you could reassure me with my latest mental battle. In the past 5-6 months, I've lost roughly 10 lbs (158.4-->148.8). I mainly maintained through July and August due to stress and lax logging and then had some slow losses during the other months. My macros weren't perfect, but my protein was always above 25% of my total intake (roughly 140 grams/day). I'm currently doing NROL Supercharged (over the Summer/Fall I was doing the Hypertrophy stage). The only cardio I do is the HIIT in the program and then whatever I get playing with my 3 young kids and taking care of our little farm.
My issue is that at the beginning of July, my BF% as calculated by the Military BF calculator was 29%. 10lbs later it is calculated as 27%. Now I realize these are simply rough estimations, but that indicates that 3-4lbs of the 10lbs lost was lean mass. I really can't imagine that this is true given that I've got more definition all over my entire body, but I'm wondering if there's something I am missing. My gut feeling is that my BF% has actually been higher all along and I didn't have as much lean mass as the calculator said and I am starting to see a more accurate number as I get leaner. Is there something I am missing here? My deficit even on my "not hungry weeks" was never more than 18% and most of the time was in the 10-15% range when I was actually in a deficit.

heybales

Huge congrats on success, even managing time periods where the focus had to change.

Bingo - usually what happens.

Also the problem using 1 calc with few measurements. That's not the waist only measurement calc, right?

Average the Navy/Military with the Covert Bailey one - they mainly use different sites.

Also, you will lose LBM, even if you retained all muscle mass.

Do you need as much blood volume for a smaller body? Nope - there goes LBM.
Do you need as much glucose stored with water if switching to lifting? Nope, there goes LBM.

You just don't want LBM to drop early (except for initial water weight of course) before you've changed size much, then it's likely some muscle mass.

Now that BF% would only have a bearing on your eating level if you used the Katch BMR as basis for TDEE levels.
In which case you'll be eating more now.
In addition to the smaller deficit you should have near the end of the journey.

BarbellCowgirl

All of that makes sense, heybales- thank you. Both of the calculators (Bailey and Military- I look at both of them for the overall trend) have given me the same scenario. CB has me at 21% and military has me at 27%. 10lbs ago, I was at 22.2% and 28%. While there is a 6 point discrepancy between the two, according to these methods my lean mass is dropping at nearly the same rate as the fat. I realize it's normal to lose some, just wasn't sure what was a typical ratio. Or if I should be looking at tweaking something to prevent this.
I was at maintenance for a few weeks over the Holidays and have gone back to a 12% deficit. We will see if this trend normalizes.