Does this muscle loss sound reasonable?

litchfieldd
litchfieldd Posts: 43 Member
in Health and Weight Loss
I'm 183 cm (6'1) and over the last 5 months or so I've dropped from 100 kg to 78.5 (21.5 kg / 47 lbs). According to my bio-impedance scales, I've also falled from a 31.4% body fat to 19.1%. According to my maths that would mean losing 16.4 kg of fat and 5.1 kg of lean mass, so for every 3 kg of fat loss I lose just under 1 kg of muscle.

I know that body fat estimates from bio-impedance is pretty inaccurate but does that kind of proportion sound reasonable?

Incidentally although a bit cardio focussed (training up for my first half-marathon), I do some although probably not enough resistance work, I keep my protein levels pretty high, and have reduced my calorie deficit over time to slow my weight loss rate down. I'm probably approaching maintenance now so trying to work out when I've cut enough, and can think about going the other way and trying to build a little muscle.

Replies

  • Missjulesdid
    Missjulesdid Posts: 1,444 Member
    I'm no expert but that is quite a bit higher than my experience so far. I don't have my exact current stats with me but I remember when I was at around the 100 pound loss mark, I had lost just under 2 pounds of muscle.. the rest was fat and excess retained water. Maybe it's different for me because I have SO MUCH weight to lose and the extra muscle loss will come later.. I do know I will definitely lose a bit more muscle before my journey is done.. I mean I was fairly active when I was over 300 pounds and as my body becomes slimmer it simply won't require quite as much muscle to haul it around.
  • litchfieldd
    litchfieldd Posts: 43 Member
    How are you estimating excess retained water? My figure for muscle loss is basically my total loss minus the 16.4 kg of fat. So I guess that 5.1 kg could include water too?
  • Missjulesdid
    Missjulesdid Posts: 1,444 Member
    My guess is yes. If you simply calculated your muscle mass by subtracting your body fat from it then your calculation would be incorrect. You lost 5.1 kg of lean body mass which is EVERYTHING in your body that is not fat, including muscle, water and any other non fatty tissue. Sorry I didn't catch how you calculated it in your original post.
    As for how retained water was estimated for me, I honestly don't know. I had my body composition professionally done.
  • litchfieldd
    litchfieldd Posts: 43 Member
    Ok, cool. Yeah, it's just a rough and ready calculation for me!

    At 100 kg and 31.4% body fat, I had 31.4 kg of fat
    At 78.5 kg and 19.1% body fat, I have 15.0 kg of fat
    So suggests I've lost 31.4 - 15.0 = 16.4 kg of fat

    That leaves unaccounted 21.5 - 16.4 = 5.1 kg of other stuff!
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    25% LBM loss is not unreasonable - it isn't optimal, resistance training can be such as to negate all loss if done over a long enough period but for a 5 month period without intensive training, it is not unexpected, in my opinion.

    A large part of that is not muscle loss - are you planning to up your training now?
  • litchfieldd
    litchfieldd Posts: 43 Member
    Thanks. I do intend to do a lot more resistance although it does tend to take a back seat against my running at the moment. I know that's not ideal for body recomposition but my NSVs from improved running fitness has been a big part mentally of sustaining the huge lifestyle changes I've made. Guess still searching for that balance!!
  • _Terrapin_
    _Terrapin_ Posts: 4,301 Member
    OP: not sure if reasonable is what I'd ask. Too much too fast? Depends on your fitness goals. What are your goals now that the weight is off?
  • IHateThinkingOfAUsername
    IHateThinkingOfAUsername Posts: 568 Member
    http://www.myfitnesspal.com/topics/show/1377010-losing-lean-muscle-mass?hl=body+fat+%+loss+muscle#posts-20972468
    I wrote this thread a little while ago asking a very similar question.

    My latest Stats (as measured by my potentially inaccurate scales):

    Starting Stats:
    41% BF
    Weight 173.5lbs

    So 71.1lbs of fat.
    102.4lbs of non-fat (muscle, bones, water etc)

    Current Stats:
    35% BF
    Weight 147lbs

    So 51.5lbs of fat.
    95.5lbs of non-fat (muscle, bones, water etc).

    So in the last 117 days I have lost:

    19.6lbs of fat.
    6.9lbs of 'other' (Some of which will be water retention - I lost 5lbs in the first week)
    At a ratio of 1:2.84
  • sandylion
    sandylion Posts: 451 Member
    Quick weight loss and a focus on running is definitely going to loose you a bunch of muscle. That doesn't sound unreasonable to me.
  • OllyJ_79
    OllyJ_79 Posts: 126 Member
    There's some images that make it easier to estimate your body fat %. Scales tend to be way way off the true amount.

    http://teaminsaneresults.com/wp-content/uploads/2013/08/Men-Body-Fat.jpg

    https://warosu.org/data/fa/img/0081/34/1398218950496.png

    Also being picky, 6ft 1 inch is actually 185.3 cm, 6ft is 183cm.
  • litchfieldd
    litchfieldd Posts: 43 Member
    OP: not sure if reasonable is what I'd ask. Too much too fast? Depends on your fitness goals. What are your goals now that the weight is off?

    Good question but not sure if I know yet! My original goals were never sharpy defined being more a) not be 'fat' or 'unfit' b) get comfortably inside healthy BMI range c) achieve a challenge - a half-marathon. I don't think I feel or look fat now, obviously fitness is a matter of perspective but I feel like I've turned the clock back 10 years and the half marathon is in about 7 weeks and pretty sure I'll be ready!

    So yes, probably time for some new ones. I'm not up for the amount of work to become really buff and do want to keep running, but I wouldn't say no to a little more strength. I guess its whether I keep losing (target loss is 0.25 to 0.5 kg per week max) for a bit longer, maybe until about 70-75 kg and then turn the corner and eat/work out to build a little muscle or whether I already at that point. Difficult to know!
  • litchfieldd
    litchfieldd Posts: 43 Member
    There's some images that make it easier to estimate your body fat %. Scales tend to be way way off the true amount.

    http://teaminsaneresults.com/wp-content/uploads/2013/08/Men-Body-Fat.jpg

    https://warosu.org/data/fa/img/0081/34/1398218950496.png

    Also being picky, 6ft 1 inch is actually 185.3 cm, 6ft is 183cm.

    Thanks. Interesting to look at. I do look slightly leaner than the 20% images so that's about consistent with the estimate.

    And thanks for being picky. I'm a bit confused but having not actually measured my height in ages I think I just had the two numbers in my head. I just measured myself and apparently I'm taller than I thought! Turns out I'm 187 cm (almost 6'2) which is a bit suprising - is it possible I've actually gained a little height!? Either way, it's improved my BMI a smidge!

    EDITED TO CORRECT A NUMBER
  • litchfieldd
    litchfieldd Posts: 43 Member
    http://www.myfitnesspal.com/topics/show/1377010-losing-lean-muscle-mass?hl=body+fat+%+loss+muscle#posts-20972468
    I wrote this thread a little while ago asking a very similar question.

    Thanks for sharing
  • IHateThinkingOfAUsername
    IHateThinkingOfAUsername Posts: 568 Member
    http://www.myfitnesspal.com/topics/show/1377010-losing-lean-muscle-mass?hl=body+fat+%+loss+muscle#posts-20972468
    I wrote this thread a little while ago asking a very similar question.

    Thanks for sharing

    You're welcome - and damn wish I could grow :)
  • Azdak
    Azdak Posts: 8,281 Member
    That sounds a little high, but not completely unreasonable. I have only seen 33+% losses of LBM in people doing HCG or who drink excessively (hard to think you can do that and still lose a lot of weight, but it's possible). But most of my test/retest subjects have engaged in some type of resistance training during their weight loss. Bodyfat scale results are more susceptible to errors based on fluid shifts, so it could be that either your start or end number was off.

    The important things are how do you look and how do you feel? The fact is that you can start weight training any time and regain any muscle you want.
  • litchfieldd
    litchfieldd Posts: 43 Member
    That sounds a little high, but not completely unreasonable. I have only seen 33+% losses of LBM in people doing HCG or who drink excessively (hard to think you can do that and still lose a lot of weight, but it's possible). But most of my test/retest subjects have engaged in some type of resistance training during their weight loss. Bodyfat scale results are more susceptible to errors based on fluid shifts, so it could be that either your start or end number was off.

    The important things are how do you look and how do you feel? The fact is that you can start weight training any time and regain any muscle you want.

    Actually I checked and realised that my initial body fat value was not from the start of my MFP journey (at 100 kg) but from a later stage when I had dropped to 93 (and probably lost a lot of water weight). Redoing the maths, puts the LBM loss at 2.5 kg out of a total loss of 14.5 kg. That's a much healthy proportion I suspect, 17% of the total loss. Apologies for the dodgy numbers earlier on - my brain doesn't really engage until the afternoon which is now is here in the UK!

    I feel great and absolutely that's what matters most! I look loads better I think, my skins looseish around the belly or at least certainly a little stretchy but I expect it will sort itself. Although I've lose 21.5 kg on MFP, over a the previous 2 or 3 years I'd broadly dropped from my worst of around 110 kg. But I am trying to weight train a bit more often, and will aim to better my current 1 or 2 sessions a week with a mix of machines and a little bit of barbell stuff but not really lifting especially heavy which I know is where I need and want to go. Although I struggle to enjoy it as much as I do running, I'm sure once I see results and progression I'll find the motivation!
  • Francl27
    Francl27 Posts: 26,371 Member
    Not sure anyone has mentioned this yet but... those scales are not accurate. It's probably way off...
  • FrenchMob
    FrenchMob Posts: 1,167 Member
    In my personal experience, I'm usually between 8-12% LBM loss, but I also do heavy strength training with some cardio. You're looking around 17-19%. It's a little higher, but not out of the ordinary.
  • FrenchMob
    FrenchMob Posts: 1,167 Member
    Not sure anyone has mentioned this yet but... those scales are not accurate. It's probably way off...
    For an exact BF% they might be (but not that bad), but for trending, they work fine.

    BTW, I did a DEXA scan last December. It said I had 35% BF, my BIA scale said 37% so it wasn't that far off.
  • Cortelli
    Cortelli Posts: 1,369 Member
    For an exact BF% they might be (but not that bad), but for trending, they work fine.

    BTW, I did a DEXA scan last December. It said I had 35% BF, my BIA scale said 37% so it wasn't that far off.

    My scale is older, but even for trending it isn't worth a damn.

    I've been getting a hydro every three months for the last year, and even sprinkled in a same-day DEXA scan as an experiment and to "validate" the hydro numbers. My older Omron scale with bio-impedance is simply worthless, both in terms of actual % and pretty much in terms of trending as well. Yes, the BF% grew smaller as I lost weight, but not anywhere near the appropriate ratio of BF% to weight, as measured by hydros and DEXAs.

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