bmi question

Hi all, cant seem to find an answer to this... my bmi is dropping and not my weight. I was happy about this but have had a few tell me that bmi does not matter, your thoughts and opinions on bmi

Replies

  • cmriverside
    cmriverside Posts: 34,416 Member
    How do you know? Did you have it professionally measured? With what kind of device? You can't really get an accurate measure at home, or even with calipers unless the person is well trained.
  • gbg49229
    gbg49229 Posts: 57
    went to a gym and met with a personal trainer who has been in the business for 17 years. He pulled out a scale that dmeasures it and said that is more accurate then anything other then a dunk tank. And from what I have read, they say they are with in 2% accurate
  • hazelsmrf
    hazelsmrf Posts: 96 Member
    I'm guessing what he meant is that he measured your body fat percentage, not BMI. BMI is a formula, a chart... there's no more accurate way, if he's talking about dunk tanks then he's talking about measuring lean body mass or body fat. And yes it's possible for your body fat to go down and your scale weight to stay the same - either through retaining water or building muscle. On the other hand, if your scale weight stays the same then so does your BMI.
  • ElizabethRoad
    ElizabethRoad Posts: 5,138 Member
    This could not happen unless you're getting taller. You must be talking about body fat %.
  • HisPathDaily
    HisPathDaily Posts: 672 Member
    Muscle weighs more, so that's good news. Fat shrinking, muscle building = body getting stronger and more fit :)

    Good for you ...
  • PittShkr
    PittShkr Posts: 1,000 Member
    I agree 1 lb of muscle weighs more than one pound of fat!
  • Jacwhite22
    Jacwhite22 Posts: 7,010 Member
    Holy crap....You must be growing taller. Congrats
  • secretlobster
    secretlobster Posts: 3,566 Member
    If your Body Fat percentage is decreasing, and not your weight, it means either:
    1) You are gaining muscle
    2) You are losing fat AND gaining muscle
  • Jacwhite22
    Jacwhite22 Posts: 7,010 Member
    went to a gym and met with a personal trainer who has been in the business for 17 years. He pulled out a scale that dmeasures it and said that is more accurate then anything other then a dunk tank. And from what I have read, they say they are with in 2% accurate

    Sounds like body fat percentage and that is not true. They use BIA and are horribly inaccurate. General guide is all they should be used for. Calipers are more accurate but dependent upon the skill of the tester (which if he said BIA was second best I would not trust....)
  • mfpcopine
    mfpcopine Posts: 3,093 Member
    I agree 1 lb of muscle weighs more than one pound of fat!

    You mean that give the same VOLUME an amount of muscle would weigh more than the same amount of fat.

    1 pound of fat = 1 pound of muscle.
  • Captain_Tightpants
    Captain_Tightpants Posts: 2,215 Member
    I would suggest finding a new trainer that talks out of the correct orifice.
  • miniragtop
    miniragtop Posts: 24 Member
    I agree 1 lb of muscle weighs more than one pound of fat!

    a pound is a pound. fat may be bulkier than muscle but it's mathematically impossible for a pound of any item to weigh more than a pound of any other item since a pound is the weight measurement.
  • SteveTries
    SteveTries Posts: 723 Member
    went to a gym and met with a personal trainer who has been in the business for 17 years. He pulled out a scale that dmeasures it and said that is more accurate then anything other then a dunk tank. And from what I have read, they say they are with in 2% accurate

    Oh my, he really said that?

    He's either conning you or is utterly clueless.

    Those scales use electrical impedence; they send a small charge into the body and measure how much is returned then apply a calculation to that to estimate bodyfat. However they are hugely affected by water retention levels which we know varies daily based on heat, health, food intake, exercise, time of month etc etc etc.
  • PittShkr
    PittShkr Posts: 1,000 Member
    I agree 1 lb of muscle weighs more than one pound of fat!

    a pound is a pound. fat may be bulkier than muscle but it's mathematically impossible for a pound of any item to weigh more than a pound of any other item since a pound is the weight measurement.


    According to everyone on MFP muscle weighs more so it must be a fact!
  • secretlobster
    secretlobster Posts: 3,566 Member
    Sorry but body fat scales are useless. For one, the electrical impulses are only traversing your LOWER body. I have a scale that measure BF% and just for S&Gs, I let it compute me this morning. It says I'm 26% but according to calipers I'm just under 20% BF. This is because I carry all of my extra fat in my lower body.

    Calipers or submersion or nothing. Scales are worthless, UNLESS you are just looking for a baseline to see if you are generally lowering your BF or not.

    Even so, the amount of water you have in your body will change the reading you get from the scales.
  • vim_n_vigor
    vim_n_vigor Posts: 4,089 Member
    Do you mean bmi or bf%? bmi is the ratio of your height and weight. I don't think it can change if your weight or height is not cahnging.
  • jcstanton
    jcstanton Posts: 1,849 Member
    I would suggest finding a new trainer that talks out of the correct orifice.

    ^^^:laugh: :laugh: :laugh:
  • Sabine_Stroehm
    Sabine_Stroehm Posts: 19,263 Member
    Do you mean bmi or bf%? bmi is the ratio of your height and weight. I don't think it can change if your weight or height is not cahnging.

    ^^This^^

    Your BMI can't change if your weight isn't changing (unless you're getting taller).
    But that your BF% is going down is good! I know mine is as well. Clothes fit very differently than they did a few months ago, since I started running again. (even though I was active before)
  • SteveTries
    SteveTries Posts: 723 Member
    Calipers or submersion or nothing.

    I pretty much agree. If you are large then the calipers are going to be challenging as it's just not that easy to grab a hold at exactly the same place each time - I use them and I think they are great and can be learnt easily enough - I don't think it gives a truly accurate BF% though, but for week to week comparative purposes it works well.

    If you are large, then I'd just use the mirror (photo's) and the measuring tape. Oh and scales. Hard to give any other advice without knowing your intake and exercise. Likely though you are not creating enough of a deficit!
  • Spice_4_Life
    Spice_4_Life Posts: 225
    I agree 1 lb of muscle weighs more than one pound of fat!

    You mean that give the same VOLUME an amount of muscle would weigh more than the same amount of fat.

    1 pound of fat = 1 pound of muscle.

    Thank you!! I friggin hate when my bf tries to tell me that muscle weighs more!! It takes up less space then fat. How do people not know that??
  • jcstanton
    jcstanton Posts: 1,849 Member
    I agree with other posters who have said to get someone to measure you with calipers, then make sure the same person measures you every time.
  • secretlobster
    secretlobster Posts: 3,566 Member
    Thank you!! I friggin hate when my bf tries to tell me that muscle weighs more!! It takes up less space then fat. How do people not know that??

    Muscle tissue is DENSER than fat tissue. So, when volume remains constant, muscle WILL weigh more.

    I really hate this argument. People always want to turn it into the stupid "what's heavier, a pound of feathers or a pound of bricks?" riddle. Learn something about science. Christ almighty.
  • librarygoddess2
    librarygoddess2 Posts: 145 Member
    I would suggest finding a new trainer that talks out of the correct orifice.

    agreed
  • krisiepoo
    krisiepoo Posts: 710 Member
    I agree 1 lb of muscle weighs more than one pound of fat!

    bwahahahahaaa
  • kristynkayte
    kristynkayte Posts: 69 Member
    I agree 1 lb of muscle weighs more than one pound of fat!
    If you had said muscle weighs more than fat I could agree. The same volume of muscle vs. same volume of fat...yes muscle will weigh more. Muscle has less volume than fat when comparing weight. BUT...a 1st grader can tell you that one pound of muscle and one pound of fat weigh the same! The volume would be different. But a pound is a pound.
  • PittShkr
    PittShkr Posts: 1,000 Member
    I agree 1 lb of muscle weighs more than one pound of fat!
    If you had said muscle weighs more than fat I could agree. The same volume of muscle vs. same volume of fat...yes muscle will weigh more. Muscle has less volume than fat when comparing weight. BUT...a 1st grader can tell you that one pound of muscle and one pound of fat weigh the same! The volume would be different. But a pound is a pound.

    theres a difference between weight, volume and mass??? uh oh
  • PittShkr
    PittShkr Posts: 1,000 Member
    I agree 1 lb of muscle weighs more than one pound of fat!
    If you had said muscle weighs more than fat I could agree. The same volume of muscle vs. same volume of fat...yes muscle will weigh more. Muscle has less volume than fat when comparing weight. BUT...a 1st grader can tell you that one pound of muscle and one pound of fat weigh the same! The volume would be different. But a pound is a pound.

    That is what everyone on here needs to realize. ^^^^ this was my exact point to the T!!!!!!! THANK YOU KRISTYNKAYTE