Goal Body Fat/Weight Equation

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songbyrdsweet
songbyrdsweet Posts: 5,691 Member
in Fitness and Exercise
I thought some people might be interested in this equation. You do need to know your current body fat to use it.

I am using myself as an example.

127 pounds, 25% +-2% body fat

127 * .25 = ~32 lbs of fat (essential and non-essential)

127-32 = 95 lbs of lean tissue (muscle, bone, skin, organs)

My goal body fat % is 19%. Here is the equation:

Lean Tissue Weight / (1-Goal Body Fat in Decimal Form)

or

95 lbs / (1-.19) = 95/.81= 117 lbs

So I will be at 19% body fat when I'm about 117 lbs. However, since there is a 2% error, that number could go up or down a couple pounds. So I have changed my goal from 125 lbs to 120 lbs.

This is a more accurate way to come up with a healthy body weight. The downside is that you do need to know your body fat %, but this can ensure you have a realistic and specific goal in mind.

Replies

  • songbyrdsweet
    songbyrdsweet Posts: 5,691 Member
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    I thought some people might be interested in this equation. You do need to know your current body fat to use it.

    I am using myself as an example.

    127 pounds, 25% +-2% body fat

    127 * .25 = ~32 lbs of fat (essential and non-essential)

    127-32 = 95 lbs of lean tissue (muscle, bone, skin, organs)

    My goal body fat % is 19%. Here is the equation:

    Lean Tissue Weight / (1-Goal Body Fat in Decimal Form)

    or

    95 lbs / (1-.19) = 95/.81= 117 lbs

    So I will be at 19% body fat when I'm about 117 lbs. However, since there is a 2% error, that number could go up or down a couple pounds. So I have changed my goal from 125 lbs to 120 lbs.

    This is a more accurate way to come up with a healthy body weight. The downside is that you do need to know your body fat %, but this can ensure you have a realistic and specific goal in mind.
  • arewethereyet
    arewethereyet Posts: 18,702 Member
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    I am so glad you posted this. When I went to the trainer she said I was 43% fat and at the end lost 4% to be 39% bf.

    I almost swallowed my teeth! I said OMG that means I have 55 pounds to lose??!! She just said no.

    I forgot you have a certain % of natural body fat (and more if you are a woman)

    I still have a ways to go, but I am getting there!!

    :flowerforyou: Jeannie
  • songbyrdsweet
    songbyrdsweet Posts: 5,691 Member
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    I am so glad you posted this. When I went to the trainer she said I was 43% fat and at the end lost 4% to be 39% bf.

    I almost swallowed my teeth! I said OMG that means I have 55 pounds to lose??!! She just said no.

    I forgot you have a certain % of natural body fat (and more if you are a woman)

    I still have a ways to go, but I am getting there!!

    :flowerforyou: Jeannie

    Yup, it's 12-15% that's essential for females. Great job losing that 4%, that didn't take long at all! :drinker:
  • RachVR6
    RachVR6 Posts: 3,688 Member
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    What if, in the process of losing weight, you put on more muscle mass?
  • nightangelstars
    nightangelstars Posts: 337 Member
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    Okay lets see . . . I'm at 134, 32% fat = 42 lbs fat, 92 lean (give or take, I'm not sure my body fat analyzer is the best). So if I aim for 20% body fat that makes my goal . . . 115 lbs.

    Well as much as I appreciate the formula, I've seen myself at 115 lbs . . . it's gross, my hip bones stuck out like the fins on an old 50's car! :laugh: I think I'll stick with my current goal of 124.
  • songbyrdsweet
    songbyrdsweet Posts: 5,691 Member
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    Well that's why it's AROUND that weight. The accuracy of your body fat measuring tool will make a difference. I was measured in the Bod Pod which has only a 2% error, but more common tools like the hand-held devices can have up to an 8% error.

    If you spent some time putting on muscle mass before you cut, your ending weight would be higher. But people here tend to throw around 'You're gaining muscle mass!' like we're all snorting growth hormone. It's not THAT easy and reaching a body fat in the teens for a female generally negates any possibility of gaining an appreciable amount of muscle mass at the same time. You need a positive nitrogen balance for that, and that only comes from excess protein, and in a caloric deficit you don't have an excess of anything.
  • RachVR6
    RachVR6 Posts: 3,688 Member
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    Well that's why it's AROUND that weight. The accuracy of your body fat measuring tool will make a difference. I was measured in the Bod Pod which has only a 2% error, but more common tools like the hand-held devices can have up to an 8% error.

    If you spent some time putting on muscle mass before you cut, your ending weight would be higher. But people here tend to throw around 'You're gaining muscle mass!' like we're all snorting growth hormone. It's not THAT easy and reaching a body fat in the teens for a female generally negates any possibility of gaining an appreciable amount of muscle mass at the same time. You need a positive nitrogen balance for that, and that only comes from excess protein, and in a caloric deficit you don't have an excess of anything.

    :laugh: :flowerforyou:
  • Iceprincessk25
    Iceprincessk25 Posts: 1,888 Member
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    Fun Fun! Apparently I'll be at 19% body fat at 138 pounds......hmmmmmmm my goal was 133-135.
  • songbyrdsweet
    songbyrdsweet Posts: 5,691 Member
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    Fun Fun! Apparently I'll be at 19% body fat at 138 pounds......hmmmmmmm my goal was 133-135.

    Well then we'll be even sexier and everyone will be jealous of us cause we're psuedo-taken. By each other. :bigsmile: :laugh:

    But of course I have to be miserably sick right now and not even approaching that. :sick: My arms do look pretty nice though from all the carbohydrates I'm not burning up. Yay glycogen. :happy:

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