Body fat % > Body mass Index
barbarinc
Posts: 2 Member
Don't pay any attention to b.m.i. It is a very vague algorithm combining height and weight. Instead find somewhere you can get your body fat percentage checked. (Preferably bio electrical impedance) it will give you a much more accurate description of where your at. Then try to lower that number. Reason being if you lose five lbs of fat, and also lose five lbs of muscle, your bmi gets a lot better because you lost 10lbs, but you aren't gaurenteed to look any better. But if you lose 5% body fat your arms will deff look sexier!
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Ok?0
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Bio electric impedance isn't any good? Changes in bf% are slow? And directly proportional to weight? So just lose the weight? Use a scale and done?0
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I assume this post was inspiredby this thread?
http://community.myfitnesspal.com/en/discussion/10363386/do-i-need-to-be-under-a-certain-bmi-to-have-sexy-arms#latest
You just recommended electrical impedance as a reliable BF measure? That's new?
There's a lot of hate going around for bmi on these boards lately but it's largely misplaced? Unless someone has significantly more or less muscle mass than average it's a fair estimate of what their target weight should be? And it's an easy number to calculate? The op of the sexy arms has significant weight to lose and trying to accurately calculate her BF% right now won't give her any additional information other than "lose more weight"? When she's closer to goal BF might come into play, but right now aiming for a healthy BMI number will put her on the right course?0 -
BMI works fine for 95% of the masses. Of course, there are outliers, but recommending BIA instead isn't the answer either. Those aren't even remotely accurate usually.0
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BMI is pretty good. It has a built in range to accomodate body types. For my height anything inside 125lb to 170lb is considered healthy, that's a pretty wide lane to get inside. Of course a few people are gonna be built lighter or heavier than that, but most people seem to overestimate healthy weight.
The basic idea that the OP proposes is right though, your body composition matters more.0 -
BMI works fine for 95% of the masses. Of course, there are outliers, but recommending BIA instead isn't the answer either. Those aren't even remotely accurate usually.
I would disagree with this in part. I think it works for 95% of the population telling you if in fact you are obese. I think that number drastically reduces when you talk about "overweight" (maybe 75%) and again when you're talking about "healthy" BMI. The reason I think that it's off for the healthy category is that there are so many people today that are "skinny fat" with our sedentary lives and have higher than recommended fat levels even though their overall weight is "normal". I do agree that BIA is not the answer either though just because it's inaccurate. But BF testing in general is what I would recommend. In order of accuracy/reliability I would say DEXA, Hydrostatic, BodPod, tape measure/scale combo, mirror, BIA. Really, the only thing I feel BIA is good for is trend tracking. If you get one of the more reliable methods done first and calibrate your BIA to match that output, I think it can have a place in your tracking metrics.0 -
BMI works fine for 95% of the masses. Of course, there are outliers, but recommending BIA instead isn't the answer either. Those aren't even remotely accurate usually.
I would disagree with this in part. I think it works for 95% of the population telling you if in fact you are obese. I think that number drastically reduces when you talk about "overweight" (maybe 75%) and again when you're talking about "healthy" BMI. The reason I think that it's off for the healthy category is that there are so many people today that are "skinny fat" with our sedentary lives and have higher than recommended fat levels even though their overall weight is "normal". I do agree that BIA is not the answer either though just because it's inaccurate. But BF testing in general is what I would recommend. In order of accuracy/reliability I would say DEXA, Hydrostatic, BodPod, tape measure/scale combo, mirror, BIA. Really, the only thing I feel BIA is good for is trend tracking. If you get one of the more reliable methods done first and calibrate your BIA to match that output, I think it can have a place in your tracking metrics.
I agree with this - it's exponentially more likely that someone would have too much fat and be inside BMI guidelines, than that someone would have the right amount of fat and be heavier than the BMI guidelines. My fiance is my height and built so much heavier than me in frame, thick wrists, wide shoulders - but there's no way he would be more than 170 muscled and cut, and I'm built thin, get up to about 135 when muscled and cut.
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Okay? Then you were overweight, no?0 -
Yet another person taking BMI too literally. BMI is an index, hence the I part. It is not a rule, not a law, but an index i.e. a guide. Similarly, the Retail Price Index (RPI) is a guide to how much prices of products will go up. That does not mean that every single product will go up in tandem, nor does it mean that RPI is bogus.
BMI works fine, just that a lot of people lack common sense to see this. They think that because THEY are classed as obese as a result of being massively built via muscle, that BMI must be ignored.
For the average person, it is absolutely fine.0 -
BMI works fine for 95% of the masses. Of course, there are outliers, but recommending BIA instead isn't the answer either. Those aren't even remotely accurate usually.
I would disagree with this in part. I think it works for 95% of the population telling you if in fact you are obese. I think that number drastically reduces when you talk about "overweight" (maybe 75%) and again when you're talking about "healthy" BMI. The reason I think that it's off for the healthy category is that there are so many people today that are "skinny fat" with our sedentary lives and have higher than recommended fat levels even though their overall weight is "normal". I do agree that BIA is not the answer either though just because it's inaccurate. But BF testing in general is what I would recommend. In order of accuracy/reliability I would say DEXA, Hydrostatic, BodPod, tape measure/scale combo, mirror, BIA. Really, the only thing I feel BIA is good for is trend tracking. If you get one of the more reliable methods done first and calibrate your BIA to match that output, I think it can have a place in your tracking metrics.
I can live with that percentage. I just think too many people say it's bunk and pretend to be outliers. In my opinion, it works. It's body mass. Wouldn't that equal fat and muscle? So it doesn't separate the two and was never intended to. You can be overweight because of muscle. Is that a bad thing? Prob not.0 -
IMO BMI is great as a way to set an initial goal range for both obese and generally overweight people. A lot of people have been obese or overweight for so long that they have no idea what a good range for their height would even be. Telling a person that she's 45% body fat and need to get down to 27% isn't helpful. It's not even very helpful to do the math and back into what the person's theoretical weight would be at that percentage because nobody loses just fat. I'd just say aim for a healthy BMI but be aware that as you near it what you see in the mirror will be a better indicator of how you're doing than will the number on the scale.0
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@eldamiano @Hornsby I completely understand that it's an index and that many of the people that comment against BMI are only looking at how it relates to them and if it doesn't work for them then it should just be thrown to the gutter.
The problem that I have with it is when it's used by doctors/insurance companies to charge higher rates. If it was only being used as a screening tool then yeah, maybe I could see it, but the fact that the group that it is the most inaccurate for is the "healthy" group is what gives me the most pause.
I don't think you can be overweight because of muscle, unless you literally have more muscle than your frame should be able to hold do to HGH or steroids.0 -
@eldamiano @Hornsby I completely understand that it's an index and that many of the people that comment against BMI are only looking at how it relates to them and if it doesn't work for them then it should just be thrown to the gutter.
The problem that I have with it is when it's used by doctors/insurance companies to charge higher rates. If it was only being used as a screening tool then yeah, maybe I could see it, but the fact that the group that it is the most inaccurate for is the "healthy" group is what gives me the most pause.
I don't think you can be overweight because of muscle, unless you literally have more muscle than your frame should be able to hold do to HGH or steroids.
Why is that the point about insurance the fault of BMI?
They could easily use another method, including yours, to determine liability....0 -
But BIA gives me laughably wrong numbers every time?0
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@eldamiano @Hornsby I completely understand that it's an index and that many of the people that comment against BMI are only looking at how it relates to them and if it doesn't work for them then it should just be thrown to the gutter.
The problem that I have with it is when it's used by doctors/insurance companies to charge higher rates. If it was only being used as a screening tool then yeah, maybe I could see it, but the fact that the group that it is the most inaccurate for is the "healthy" group is what gives me the most pause.
I don't think you can be overweight because of muscle, unless you literally have more muscle than your frame should be able to hold do to HGH or steroids.
I disagree somewhat. I do believe you can be overweight because of muscle. Other than that, we're on the same page.0 -
@eldamiano because that's what it is primarily used for! It's not that much more difficult to break out the tape measure and take a few waist measurements. It's just not good math coming from an engineer. The algorithm was developed by an economist to fit a group of data points as they related to an entire population. He's even quoted as saying that it should never be used to assess individual health!0
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@eldamiano because that's what it is primarily used for! It's not that much more difficult to break out the tape measure and take a few waist measurements. It's just not good math coming from an engineer. The algorithm was developed by an economist to fit a group of data points as they related to an entire population. He's even quoted as saying that it should never be used to assess individual health!
Yes, the CDC says it is meant to be used as a screening and if an individual is classed in a category that would include a health risk, that further assessments be done.
I've been through an assessment at work where I was classed as overweight by BMI. The nurse then used another method that included my waist size and classed me as healthy.0 -
The BMI is really for large swaths of population. Using it for individuals is really useless in my opinion. I'm borderline Obese at 190 and 5'8". It assumes you are a very low muscle massed individual and a very significant portion of your weight is coming from fat.0
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Bio-Electrical Impedance is nice to see trends, but it isn't reliable as an actual body fat % estimate.
There are varying numbers that give different results. For example, this is what my results looked like recently:
Scale w/ Bio-electrical impedance with 4 contacts (2 hands, 2 feet): 23.7%
Calipers: 20.7%
Military body fat calculation: 16.83%
Covert-Baily body fat calculation: 12.2%
As you can see, the bio-electrical impedance method is the highest and is almost twice the lowest estimate. Reality is probably somewhere in between.0 -
CasperNaegle wrote: »The BMI is really for large swaths of population. Using it for individuals is really useless in my opinion. I'm borderline Obese at 190 and 5'8". It assumes you are a very low muscle massed individual and a very significant portion of your weight is coming from fat.
Exactly what CasperNaegle said. BMI was not meant for individuals. It was meant for entire populations. I also "loathe" when people ask me my weight and then compare it to BMI. For me (5' 9") my BMI says I need to be 168 lbs to be below "overweight". However, when I weigh 168 lbs, my family is begging me to eat, because my face is extremely drawn and I look undernourished (Body fat was between 17% - 18% and my waistline was 33"). I have bigger, muscular thighs and calves, and likely thicker bones, and these wreak havoc on the scale.0 -
I find body fat calculators to be rather inaccurate. That being said, I have never done the specific method mentioned. I just find them inaccurate because I'm wearing a size 2-4 and its telling me I'm at risk of being over weight (I'm 5'5" , 138lbs). I had also lost two inches off my waist and my body fat percentage didn't even drop a fraction of a precent.0
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@eldamiano because that's what it is primarily used for! It's not that much more difficult to break out the tape measure and take a few waist measurements. It's just not good math coming from an engineer. The algorithm was developed by an economist to fit a group of data points as they related to an entire population. He's even quoted as saying that it should never be used to assess individual health!
Again, why is that the fault of BMI as a guide? The OP referred to it as a vague algorithm, without any reference to insurance premiums, hence my post. This is even though I disagree with what it is used for. I have heard of BMI thousands of times in general use without it being in the context of insurance.0 -
BMI works fine for 95% of the masses. Of course, there are outliers, but recommending BIA instead isn't the answer either. Those aren't even remotely accurate usually.
I would disagree with this in part. I think it works for 95% of the population telling you if in fact you are obese. I think that number drastically reduces when you talk about "overweight" (maybe 75%) and again when you're talking about "healthy" BMI. The reason I think that it's off for the healthy category is that there are so many people today that are "skinny fat" with our sedentary lives and have higher than recommended fat levels even though their overall weight is "normal". I do agree that BIA is not the answer either though just because it's inaccurate. But BF testing in general is what I would recommend. In order of accuracy/reliability I would say DEXA, Hydrostatic, BodPod, tape measure/scale combo, mirror, BIA. Really, the only thing I feel BIA is good for is trend tracking. If you get one of the more reliable methods done first and calibrate your BIA to match that output, I think it can have a place in your tracking metrics.
Actually, BMI is 100% accurate at telling someone they are obese or overweight. BMI is used to define those terms, medically. It becomes less clear below obese BMI's if the BMI is a predictor of health, or of body fat percentage. Which is fine, nothing in medical literature says that overweight is a guarantee a person is unhealth, or that normal weight is healthy.0 -
Codyroo5539 wrote: »CasperNaegle wrote: »The BMI is really for large swaths of population. Using it for individuals is really useless in my opinion. I'm borderline Obese at 190 and 5'8". It assumes you are a very low muscle massed individual and a very significant portion of your weight is coming from fat.
Exactly what CasperNaegle said. BMI was not meant for individuals. It was meant for entire populations. I also "loathe" when people ask me my weight and then compare it to BMI. For me (5' 9") my BMI says I need to be 168 lbs to be below "overweight". However, when I weigh 168 lbs, my family is begging me to eat, because my face is extremely drawn and I look undernourished (Body fat was between 17% - 18% and my waistline was 33"). I have bigger, muscular thighs and calves, and likely thicker bones, and these wreak havoc on the scale.
How can it be accurate for populations if it doesn't have at least a modicum of accuracy at individual level?
You're speaking as if 17-18% is unhealthy low, assuming you have an accurate source for the number. People's perceptions of what is too thin is rather skewed these days by a population where the majority are overweight or obese.0
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