impedance scale to measure body fat

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rjbraun
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impedance scale to measure body fat

Post by rjbraun »

Is an impedance scale worth buying? I wasn't aware of them until recently. I would be interested to measure body fat, but if the scale is not so accurate I'm not sure I'll find it so useful. Based on a quick search this one on Amazon seems to get good reviews. It costs more than I would like to spend. I can afford it, but I am also actively trying to cut down on accumulating "stuff". So, if it's something I'll use a couple of times but will then have doubts about its accuracy, it's probably not a good purchase for me. That said, a bathroom scale we bought a couple of years ago was money well spent, somewhat to my surprise.

https://www.amazon.com/Omron-Body-Compo ... r=8-5&th=1

One more thought. Maybe I would be better off visiting a "fitness specialist" for a body composition test. I'm unlikely to do that anytime soon, though, given covid conditions in my area as well as other priorities and limited time. Also, spending 80 bucks on the monitor / scale sold on Amazon would probably be a drop in the bucket compared to the expense and time of seeing a fitness trainer / specialist.
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mrmass
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Re: impedance scale to measure body fat

Post by mrmass »

Go "analog" with some calipers. Just like we used in high school.
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muffins14
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Re: impedance scale to measure body fat

Post by muffins14 »

The more reviews I read for those scales on amazon, the less confident I was that any of the models would give good results. If anything, you might get lucky and get a model that is consistent and precise but not accurate, so you can use it to track changes over time even if the reported number is too high/low.

Perhaps you can be satisfied with knowing on your weight is moving in some direction and that you look better in the mirror?
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Sandtrap
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Re: impedance scale to measure body fat

Post by Sandtrap »

Another measurement of excess body fat:
**Purely analog.

When driving down a "washboard" road, gravel or asphalt or dirt. . .

What ever is shaking and bouncing is expendable body fat. . .

This has worked well for many decades.

One of a zillion ways of doing things (dis laimer) :shock: :shock:
j :D

In the past:
Calipers
Digital Scale
Doctor's office BMI eval
etc.
Last edited by Sandtrap on Wed May 11, 2022 9:32 am, edited 1 time in total.
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H-Town
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Re: impedance scale to measure body fat

Post by H-Town »

mrmass wrote: Wed May 11, 2022 8:34 am Go "analog" with some calipers. Just like we used in high school.
https://www.livestrong.com/article/3780 ... surements/
^ this. I've been using calipers ever since. It's the most consistent tool to measure body fat by far. You can get it for $5-$9 on amazon.
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Watty
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Re: impedance scale to measure body fat

Post by Watty »

Someone mentioned consistency.

Be aware that some bathroom scales will stealthy remember your weight and if you step off it then step on it again they will show you the same weight down to the decimal point just to give you the appearance of consistency.

I got a new scale recently and it does that. I have weighted myself, stepped off and picked up something that weights around a pound, and when stepped back on it the scales showed the exact weight that it did the first time.
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TierArtz
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Re: impedance scale to measure body fat

Post by TierArtz »

I use Tanita body fat (and total body water) scales. The last one purchased was $60 in 2015; the one before that was $160 in 2000. I believe it is accurate as after a run or mowing the grass, it shows increased fat and decreased water. After hydrating again, things stabilize. I trust the body fat reading when hydrated (about 52% TBW).

If full body, vs segmental, composition is the goal, this model from Competitive Edge (their consumer storefront) looks good for $99: https://www.thecompetitiveedge.com/shop ... 50150.html

Just tested mine for consistency - same weight on two tries, but a few tenths higher after picking up a small book.

If you are going to use it to weigh packages for shipping, Tanita has a beep (when finished) and hold the reading feature; works great for weighing large boxes that completely cover the scale.
stoptothink
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Re: impedance scale to measure body fat

Post by stoptothink »

Biolectrical impedence is a pretty inaccurate way to assess bodyfat. Under normal conditions it is generally 3%-8% off, but there are many factors (especially hydration and recent food intake) that can throw it way off. We've done anecdotal tests in our facility where the same person's BI bodyfat results were different by 30%+, on the same day under different conditions. IMO, they are pretty much useless unless you are testing yourself under the exact same conditions all the time.

Ask yourself why you want to regularly assess your bodyfat. If you really are determined, find a DEXA near you.
wunder
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Re: impedance scale to measure body fat

Post by wunder »

I've had a Withings Body Comp scale since 2013 or so with I believe this method for bodyfat assessment. As others have noted there is some variance as by playing with hydration levels (say running 10 miles in the heat without drinking water) I can throw off the percentage by 5% or more.

However, over long periods of time I think it does a pretty good job of trending and I have logs of my weight and rough body fat numbers going back almost a decade now. For consistency I always weigh myself first thing in the morning after using the toilet but before eating or drinking. Within that context of tracking trends I think it is nice to have.

But if you are trying to get an "accurate" number for a specific purpose I wouldn't trust it.
hunoraut
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Re: impedance scale to measure body fat

Post by hunoraut »

My withings gives me a 200bps window of variance over a short time time, ranging from 14-16%, so its pretty noisy measurement IMO
mrb09
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Re: impedance scale to measure body fat

Post by mrb09 »

I have a Withings scale, and I take the body fat measurement with a grain of salt, but it has a water percentage measurement that seems to be at least roughly accurate -- if I get dehydrated, then I see it go down, and if I hydrate, it goes back up. I've been on a weight loss/exercise program for the last six months, and although the water measurement fluctuates daily with my hydration level, it has gone up over time, consistent with fat loss/muscle gain.
heywhoathere
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Re: impedance scale to measure body fat

Post by heywhoathere »

Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
Last edited by heywhoathere on Wed May 11, 2022 12:01 pm, edited 1 time in total.
stoptothink
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Re: impedance scale to measure body fat

Post by stoptothink »

heywhoathere wrote: Wed May 11, 2022 11:52 am Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
Actually, in the healthcare sphere we are moving more towards analyzing bodyfat because it is a significantly better predictor of cardiometabolic health than BMI (due to contemporary research like this https://pubmed.ncbi.nlm.nih.gov/32482372/). But, that is of course because BMI is a really poor predictor, on the individual level. Totally agree otherwise, first question should be asking why it is you want to regularly track bodyfat.
heywhoathere
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Re: impedance scale to measure body fat

Post by heywhoathere »

stoptothink wrote: Wed May 11, 2022 11:57 am
heywhoathere wrote: Wed May 11, 2022 11:52 am Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
Actually, in the healthcare sphere we are moving more towards analyzing bodyfat because it is a significantly better predictor of overall (individual) health
Fair enough and I edited my original post. Maybe saying "overall fitness" would be more accurate than "overall health"? Although I guess that would only be relevant for someone near the "normal" bodyfat range.
sil2017
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Re: impedance scale to measure body fat

Post by sil2017 »

I don't think it is very accurate.

Best is check your body in front of the mirror and be honest with yourself.

You can always try the self pinch test.
H-Town
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Re: impedance scale to measure body fat

Post by H-Town »

heywhoathere wrote: Wed May 11, 2022 11:52 am Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
I see bodybuilders track body fat when competing. But many also have a very unhealthy obsession with body fat, in a way that it gets unhealthy to get their body fat below certain level. It impacts gut issue, hormone, and many other issues.

I agree with you that many people would benefit from just building lean muscle mass. In my opinion, strength is a much better indicator of overall fitness. For example, you can test grip strength as an indicator of overall health.
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rjbraun
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Re: impedance scale to measure body fat

Post by rjbraun »

stoptothink wrote: Wed May 11, 2022 9:38 am Biolectrical impedence is a pretty inaccurate way to assess bodyfat. Under normal conditions it is generally 3%-8% off, but there are many factors (especially hydration and recent food intake) that can throw it way off. We've done anecdotal tests in our facility where the same person's BI bodyfat results were different by 30%+, on the same day under different conditions. IMO, they are pretty much useless unless you are testing yourself under the exact same conditions all the time.

Ask yourself why you want to regularly assess your bodyfat. If you really are determined, find a DEXA near you.
Actually, I had a DEXA done recently, but I can't find bodyfat results in the several page report I received. (A google search showed where the information is in a sample report, but I didn't find anything comparable in mine.)

Do you know whether the lab that performed the DEXA would likely have the information stored somewhere? In other words, is bodyfat "automatically" measured in a DEXA, and it's a question of what the lab chooses to display in its report, or is it a result that the lab would need to actively seek to measure when initiating a DEXA? I am wondering whether to try to contact the lab to see if they would release the information to me, if it's available.

As to your question, I guess I am kind of curious to know my current bodyfat and then to see how it may change over time (assuming I make a concerted effort to lower it). I feel my bodyfat is higher than desirable (for both good health and personal preference), but from a weight / BMI standpoint things are "fine".
stoptothink
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Re: impedance scale to measure body fat

Post by stoptothink »

rjbraun wrote: Wed May 11, 2022 12:19 pm
stoptothink wrote: Wed May 11, 2022 9:38 am Biolectrical impedence is a pretty inaccurate way to assess bodyfat. Under normal conditions it is generally 3%-8% off, but there are many factors (especially hydration and recent food intake) that can throw it way off. We've done anecdotal tests in our facility where the same person's BI bodyfat results were different by 30%+, on the same day under different conditions. IMO, they are pretty much useless unless you are testing yourself under the exact same conditions all the time.

Ask yourself why you want to regularly assess your bodyfat. If you really are determined, find a DEXA near you.
Actually, I had a DEXA done recently, but I can't find bodyfat results in the several page report I received. (A google search showed where the information is in a sample report, but I didn't find anything comparable in mine.)

Do you know whether the lab that performed the DEXA would likely have the information stored somewhere? In other words, is bodyfat "automatically" measured in a DEXA, and it's a question of what the lab chooses to display in its report, or is it a result that the lab would need to actively seek to measure when initiating a DEXA? I am wondering whether to try to contact the lab to see if they would release the information to me, if it's available.

As to your question, I guess I am kind of curious to know my current bodyfat and then to see how it may change over time (assuming I make a concerted effort to lower it). I feel my bodyfat is higher than desirable (for both good health and personal preference), but from a weight / BMI standpoint things are "fine".
Depends on if it was a whole body scan. Unless it was performed specifically for the purpose of examining body composition, a DEXA usually is focused only on the lumbar spine and hips.
quantAndHold
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Re: impedance scale to measure body fat

Post by quantAndHold »

I have a Tanita scale that I got back in the 90’s. It isn’t accurate, in the sense that if the scale says 20%, then I believe my body fat is actually 20%. But it is internally consistent with itself over time. I’ve tracked several years worth of weight and body fat readings in Apple Health, and can see them going up and down as my fitness goes up and down. It’s more convenient than doing a caliper test or going out for a Dexa scan, and the sensitivity is higher than looking in the mirror or pinching an inch. So I find it useful. But I would never claim that it’s particularly accurate.

If I were getting a new scale today, I would get one of the ones with the paddles you hold in your hands. Those are apparently more accurate than the scale I have, which just has little pads to put my bare feet on.
Yes, I’m really that pedantic.
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rjbraun
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Re: impedance scale to measure body fat

Post by rjbraun »

stoptothink wrote: Wed May 11, 2022 12:30 pm Depends on if it was a whole body scan. Unless it was performed specifically for the purpose of examining body composition, a DEXA usually is focused only on the lumbar spine and hips.
Thank you - that's helpful, much appreciated.
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Re: impedance scale to measure body fat

Post by jjbychko »

I have a Withings Body+. It's a nice scale but the body fat measurement is not accurate. The scale I use at the gym measures impedance through both your hands a feet and is much more accurate. As far as calipers go, they only measure the subcutaneous fat. By far the worst fat on your body is visceral fat. Visceral fat is deep in the body near your organs. I see many (if not most) gym goers both young and old with visceral fat. It shows as the bulging belly. You can not spot reduce this. Getting rid of excess body fat is probably 60% diet and 40% exercise.
livesoft
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Re: impedance scale to measure body fat

Post by livesoft »

I am really wondering what is the purpose of knowing more than a rough estimate of this number? Suppose one had a device that gave one an accurate number: What would one do with that knowledge? Why wouldn't one's accurate weight be a suitable proxy for this number? Or if one is interested in "visceral fat" in the location around one's belly button, then a simply pinch test gives you all the knowledge that you can probably use. :)

From weight & BMI, I am skinny. But from eating oatmeal and the exercises associated with that, I like the look of my abs.
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H-Town
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Re: impedance scale to measure body fat

Post by H-Town »

livesoft wrote: Wed May 11, 2022 1:38 pm I am really wondering what is the purpose of knowing more than a rough estimate of this number? Suppose one had a device that gave one an accurate number: What would one do with that knowledge? Why wouldn't one's accurate weight be a suitable proxy for this number? Or if one is interested in "visceral fat" in the location around one's belly button, then a simply pinch test gives you all the knowledge that you can probably use. :)
It probably has more meaning to a group of people who like to track data and manage it. It could also be a means to an end if it helps people become healthier. I just speculate here...
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InMyDreams
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Re: impedance scale to measure body fat

Post by InMyDreams »

If you have a local university exercise science department, see if they offer body fat testing. Some may offer Bod Pod/Air Displacement, others may offer hydrostatic weighing
https://www.sportsperformancebulletin.c ... d-bod-pod/

But, as others have mentioned, why? I followed for a while, and if it spurs you on to work out/lose weight - great. I was always skeptical of impedance scales. Which ever method you use, you must follow the pre-measure rules carefully.
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Re: impedance scale to measure body fat

Post by quantAndHold »

livesoft wrote: Wed May 11, 2022 1:38 pm I am really wondering what is the purpose of knowing more than a rough estimate of this number? Suppose one had a device that gave one an accurate number: What would one do with that knowledge? Why wouldn't one's accurate weight be a suitable proxy for this number? Or if one is interested in "visceral fat" in the location around one's belly button, then a simply pinch test gives you all the knowledge that you can probably use. :)

From weight & BMI, I am skinny. But from eating oatmeal and the exercises associated with that, I like the look of my abs.
I find it useful to know whether that number is going up, down, or sideways over time, to see how well my diet or workout routine is working. The pinch test is too gross a measurement to tell me anything very useful.
Yes, I’m really that pedantic.
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rjbraun
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Re: impedance scale to measure body fat

Post by rjbraun »

OP here. Thanks everyone for the interesting commentary and helpful feedback. You all convinced me, I won't get an impedance scale, at least no time soon. I could almost see getting the calipers, but for my purposes the "pinch test" will be fine for the time being. I don't have the discipline and patience now to take and record caliper readings. I also think I would just feel discouraged when the numbers don't drop, at least not in the unrealistic timeframe I might impose. :wink:
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Cheez-It Guy
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Re: impedance scale to measure body fat

Post by Cheez-It Guy »

Watty wrote: Wed May 11, 2022 9:07 am Someone mentioned consistency.

Be aware that some bathroom scales will stealthy remember your weight and if you step off it then step on it again they will show you the same weight down to the decimal point just to give you the appearance of consistency.

I got a new scale recently and it does that. I have weighted myself, stepped off and picked up something that weights around a pound, and when stepped back on it the scales showed the exact weight that it did the first time.
My scale does this. So annoying. I have mine in a walk-in closet, so I will step on and grab three pairs of pants on hangers off the rod within arm's reach of the scale, then step off and back on without them to get an accurate weight. I don't understand the point of this. I notified the manufacturer years ago, who predictably was of no help. I guess I can work around it, but I don't understand it.
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rjbraun
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Re: impedance scale to measure body fat

Post by rjbraun »

stoptothink wrote: Wed May 11, 2022 11:57 am
heywhoathere wrote: Wed May 11, 2022 11:52 am Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
Actually, in the healthcare sphere we are moving more towards analyzing bodyfat because it is a significantly better predictor of cardiometabolic health than BMI (due to contemporary research like this https://pubmed.ncbi.nlm.nih.gov/32482372/). But, that is of course because BMI is a really poor predictor, on the individual level. Totally agree otherwise, first question should be asking why it is you want to regularly track bodyfat.
Interesting, this is what my gut (haha, no pun intended) tells me. My BMI is "normal" but on the lower end of the range. If I mention my weight when I go for an annual checkup, my doctor will say I am fine. They will even imply or explicitly state that I should not lose weight. And I don't particularly want to lose weight, but I think I could build more muscle, be better toned, etc. And I am somewhat concerned that my body fat may be on the high end, especially given my relatively small frame / build. So, yeah, what you, or the NIH study you cited (which I didn't really read), said speaks to my motivation to assess my body fat composition. :happy
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Re: impedance scale to measure body fat

Post by rjbraun »

duplicate
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rjbraun
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Re: impedance scale to measure body fat

Post by rjbraun »

Cheez-It Guy wrote: Wed May 11, 2022 8:40 pm
Watty wrote: Wed May 11, 2022 9:07 am Someone mentioned consistency.

Be aware that some bathroom scales will stealthy remember your weight and if you step off it then step on it again they will show you the same weight down to the decimal point just to give you the appearance of consistency.

I got a new scale recently and it does that. I have weighted myself, stepped off and picked up something that weights around a pound, and when stepped back on it the scales showed the exact weight that it did the first time.
My scale does this. So annoying. I have mine in a walk-in closet, so I will step on and grab three pairs of pants on hangers off the rod within arm's reach of the scale, then step off and back on without them to get an accurate weight. I don't understand the point of this. I notified the manufacturer years ago, who predictably was of no help. I guess I can work around it, but I don't understand it.
My scale readings also seem kind of surprising at times. Will have to keep closer tabs on things going forward, including intentionally adding / removing weighted items. Thank you both for the heads-up.
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Cheez-It Guy
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Re: impedance scale to measure body fat

Post by Cheez-It Guy »

What I found is that if my weight varies within a tight but still variable range, the scale will show exactly the same weight reading across multiple days. Only by picking up enough weight to trigger a change (or naturally fluctuating enough) can I "trick" the scale into forgetting the last value it settled on. Then I drop the extra weight and step on for the accurate current weight. This is not a fancy scale with lots of settings or an advertised memory function. It's a Taylor digital scale that runs on a CR2032 battery with no buttons and only a toggle switch on the back to change units between pounds and kilograms.
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Re: impedance scale to measure body fat

Post by livesoft »

quantAndHold wrote: Wed May 11, 2022 5:31 pmI find it useful to know whether that number is going up, down, or sideways over time, to see how well my diet or workout routine is working. The pinch test is too gross a measurement to tell me anything very useful.
My weight fluctuations follow my diet and workout fluctuations rather closely, but only when I weigh myself in the mornings before eating breakfast and after eliminating excess weight.
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InMyDreams
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Re: impedance scale to measure body fat

Post by InMyDreams »

BMI was developed to describe populations, not individuals

"Keys explicitly judged BMI as appropriate for population studies and inappropriate for individual evaluation."
https://en.wikipedia.org/wiki/Body_mass_index
randomguy
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Re: impedance scale to measure body fat

Post by randomguy »

H-Town wrote: Wed May 11, 2022 1:43 pm
livesoft wrote: Wed May 11, 2022 1:38 pm I am really wondering what is the purpose of knowing more than a rough estimate of this number? Suppose one had a device that gave one an accurate number: What would one do with that knowledge? Why wouldn't one's accurate weight be a suitable proxy for this number? Or if one is interested in "visceral fat" in the location around one's belly button, then a simply pinch test gives you all the knowledge that you can probably use. :)
It probably has more meaning to a group of people who like to track data and manage it. It could also be a means to an end if it helps people become healthier. I just speculate here...
Weight is a poor proxy. If you lose 10lbs of muscle and gain 10lbs of fat, your weight stays the same. Your health doesn't. Same thing is you lose weight by calcium depleting your bones.

That being said I don't know if any of the scales are remotely accurate enough to be of any use.
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Re: impedance scale to measure body fat

Post by livesoft »

randomguy wrote: Thu May 12, 2022 12:35 amWeight is a poor proxy. If you lose 10lbs of muscle and gain 10lbs of fat, your weight stays the same. Your health doesn't. Same thing is you lose weight by calcium depleting your bones.
Are folks saying that knowing "impedance" is going to tell one that, but looking in the mirror will not?
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stoptothink
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Re: impedance scale to measure body fat

Post by stoptothink »

InMyDreams wrote: Thu May 12, 2022 12:23 am BMI was developed to describe populations, not individuals

"Keys explicitly judged BMI as appropriate for population studies and inappropriate for individual evaluation."
https://en.wikipedia.org/wiki/Body_mass_index
Yes, it is a population health metric, but because of its convenience it has been used for individual health determinations. Recent research is providing evidence of how poor BMI is when used for individuals; ie https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009819/. Most recent studies show that those in the "overweight" category (25-30 BMI) tend to have the longest healthspan and lifespan. This is likely because because they carry the most lean muscle tissue - this is the category where most "athletes" fall into. It's (obviously) more beneficial to your metabolic health to be a little "overweight" but lean and muscular, then a "healthy" BMI but with little muscle mass and carrying some adipose.

It's been fun trying to convince my colleagues that research suggesting that metrics of strength (grip strength, pushup maximum efforts) are just as effective at predicting risk for metabolically-related disease and healthspan as Vo2max and RHR is valid, and that we need to encourage our patients to include some form of strength training into their lifestyle.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6778477/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6484614/
https://www.tandfonline.com/doi/full/10 ... 20.1748220

Oh man, don't get me started on Ancel Keyes (although I clearly agree on his statement here).
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Re: impedance scale to measure body fat

Post by jjbychko »

livesoft wrote: Wed May 11, 2022 1:38 pm I am really wondering what is the purpose of knowing more than a rough estimate of this number? Suppose one had a device that gave one an accurate number: What would one do with that knowledge? Why wouldn't one's accurate weight be a suitable proxy for this number? Or if one is interested in "visceral fat" in the location around one's belly button, then a simply pinch test gives you all the knowledge that you can probably use. :)

From weight & BMI, I am skinny. But from eating oatmeal and the exercises associated with that, I like the look of my abs.
For me it's an indication of progress. The measurement lets me know if I am doing enough particularly with my diet. I work out 5-6 times a week. I never use to track this information. I'd run, lift weights yet I still had stomach bulge. I took a training session which included measurements. Now that I measure, I've reduced my body fit finally into the teens and dropped 15 pounds. It definitely is a reminder of my progress. It's a retirement hobby for me.
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Re: impedance scale to measure body fat

Post by lgs88 »

livesoft wrote: Wed May 11, 2022 1:38 pm

From weight & BMI, I am skinny. But from eating oatmeal and the exercises associated with that, I like the look of my abs.
livesoft, would you please fill us in on the exercises associated with eating oatmeal? I am picturing a weighted spoon, or perhaps a simulated high-gravity environment to increase the level of resistance.

In all seriousness to the OP — I wouldn’t bother with such a device for the home. Having it around will probably mean using it frequently, and day-to-day fluctuations in weight and body fat are no more meaningful than day-to-day fluctuations in the market. The medium and long-term trend is what counts.

What I might do is schedule a bimonthly check-in using the impedance scale at a commercial gym. I believe Anytime Fitness includes these assessments periodically with every membership.

I should add that money spent seeing a trainer/buying a gym membership can be a great investment or a poor investment, depending on how you use it. I value my health highly and I bet you do too, but buying the membership alone doesn’t do the trick!
merely an interested amateur
quantAndHold
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Re: impedance scale to measure body fat

Post by quantAndHold »

livesoft wrote: Thu May 12, 2022 5:21 am
randomguy wrote: Thu May 12, 2022 12:35 amWeight is a poor proxy. If you lose 10lbs of muscle and gain 10lbs of fat, your weight stays the same. Your health doesn't. Same thing is you lose weight by calcium depleting your bones.
Are folks saying that knowing "impedance" is going to tell one that, but looking in the mirror will not?
As a postmenopausal woman, I’m always going to have plenty to pinch, my abs disappeared long ago, and pants that are made for women of my generation have enough spandex in them that they feel about the same through a fairly wide range of possibilities. Body fat % gives me a much better idea of what’s going on underneath all that.

For someone who’s just trying to lose 40 pounds, a regular scale is probably plenty. But as a competitive athlete who’s already at my target weight, it’s the easiest way to get feedback about my training.
Yes, I’m really that pedantic.
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somewhatentertained
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Re: impedance scale to measure body fat

Post by somewhatentertained »

Sandtrap wrote: Wed May 11, 2022 8:41 am When driving down a "washboard" road, gravel or asphalt or dirt. . .
What ever is shaking and bouncing is expendable body fat. . .
:D thanks for the giggle Sandtrap, this is my method :sharebeer
livesoft
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Re: impedance scale to measure body fat

Post by livesoft »

lgs88 wrote: Fri May 13, 2022 10:14 amlivesoft, would you please fill us in on the exercises associated with eating oatmeal? I am picturing a weighted spoon, or perhaps a simulated high-gravity environment to increase the level of resistance.
It looks like you joined the Bogleheads forum very recently about 6 years ago, so perhaps you didn't catch this thread:
viewtopic.php?p=2242092#p2242092
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dogbones
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Re: impedance scale to measure body fat

Post by dogbones »

stoptothink wrote: Wed May 11, 2022 11:57 am
heywhoathere wrote: Wed May 11, 2022 11:52 am Unless you're trying to compete in bodybuilding, I don't think bodyfat is a particularly useful metric to track in terms of measuring overall health. You're better off focusing on building lean muscle mass and tracking progress visually through progress pictures.

If you're just interested in knowing your bodyfat %, finding a place local to you that offers something like a DEXA or Bod Pod scan is your best bet. Or as others suggested. learning how to take the measurements physically with calipers. The scales you can buy for your home are wildly inaccurate.
Actually, in the healthcare sphere we are moving more towards analyzing bodyfat because it is a significantly better predictor of cardiometabolic health than BMI (due to contemporary research like this https://pubmed.ncbi.nlm.nih.gov/32482372/). But, that is of course because BMI is a really poor predictor, on the individual level. Totally agree otherwise, first question should be asking why it is you want to regularly track bodyfat.
This is refreshing to hear (moving away from BMI). BMI is still stamped on my children's paperwork and I choose to ignore it because I understand it's insignificance to their overall health. But this isn't true for the entire population who are told it's critical factor in identifying obesity, prescribing medication, etc.

OP to offer my advice:
The skinfold analysis, bioimpedance scale and underwater weighing are three of the most accurate ways to measure body composition and body fat. Body fat measurements are important for a lot of populations, not just bodybuilding. Start with a skinfold caliper, but have someone else do it for you as you will not be able to reach the subscapular or tricep locations with accuracy.
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Re: impedance scale to measure body fat

Post by BespokeBiker »

+1 for Tanita scale (measuring Weight / Body Fat / Body Water )

I'm an active bike rider and have kept a semi-regular log of my Weight & Body fat for over 7 yrs. (***)
For me the Tanita scale is consistent if I measure after a shower, when the soles of my feet are damp, and when I'm hydrated
1) Weight is very accurate.
2) Body Fat -- Tanita addresses how their measure of Bioelectrical Impedance will fluctuate with relative body hydration.

So if you're seeking a precisely accurate number for Body Fat percentage, Bioelectrical Impedance is NOT THE MOST ACCURATE METHOD. But I find the Impedence readings I get are consistent with fluctuations in my weight - and make sense compared to clinical study-based expected ranges. So for me, using Impedance readings as an indication of my body fat has been "GOOD ENOUGH".

(***) Over the years it's been fascinating to see how my weight will fluctuate through the 4 seasons in a regular way
Last edited by BespokeBiker on Sat May 14, 2022 2:54 am, edited 3 times in total.
livesoft
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Re: impedance scale to measure body fat

Post by livesoft »

BespokeBiker wrote: Fri May 13, 2022 7:24 pm (***) Over the years it's been fascinating to see how my weight will fluctuate through the 4 seasons in a regular way
If your weight fluctuates like mine, then it goes up in October leading to Halloween, continues up through Thanksgiving and December hoidays, then decreases to March and stays steady until October.
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Afty
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Re: impedance scale to measure body fat

Post by Afty »

A few years ago I had a DEXA body composition scan out of curiosity. My body fat was higher than I expected given that I was pretty fit and marathon training at the time. My sense is that other methods tend to read low and that DEXA is most accurate.
Caduceus
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Re: impedance scale to measure body fat

Post by Caduceus »

Is "body fat" very different from "visual fat"? As in, is it possible for someone to look fat but have low body fat, or for someone to be skinny and have high body fat? If not, then wouldn't looking in the mirror be good enough as an approximation?
getthatmarshmallow
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Re: impedance scale to measure body fat

Post by getthatmarshmallow »

stoptothink wrote: Thu May 12, 2022 6:15 am
InMyDreams wrote: Thu May 12, 2022 12:23 am BMI was developed to describe populations, not individuals

"Keys explicitly judged BMI as appropriate for population studies and inappropriate for individual evaluation."
https://en.wikipedia.org/wiki/Body_mass_index
Yes, it is a population health metric, but because of its convenience it has been used for individual health determinations. Recent research is providing evidence of how poor BMI is when used for individuals; ie https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8009819/. Most recent studies show that those in the "overweight" category (25-30 BMI) tend to have the longest healthspan and lifespan. This is likely because because they carry the most lean muscle tissue - this is the category where most "athletes" fall into. It's (obviously) more beneficial to your metabolic health to be a little "overweight" but lean and muscular, then a "healthy" BMI but with little muscle mass and carrying some adipose.

It's been fun trying to convince my colleagues that research suggesting that metrics of strength (grip strength, pushup maximum efforts) are just as effective at predicting risk for metabolically-related disease and healthspan as Vo2max and RHR is valid, and that we need to encourage our patients to include some form of strength training into their lifestyle.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6778477/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6484614/
https://www.tandfonline.com/doi/full/10 ... 20.1748220

Oh man, don't get me started on Ancel Keyes (although I clearly agree on his statement here).

Isn't there some evidence that the observed positive effect of 25-30 BMI was largely that it's protective in the elderly/very ill, and not therefore generally better than 18-24? (Just curious. )

OP, if you're near a university that has a sports program you might be able to get a scan for not too much money. For me, tape measure/visual cues work, but I've been in a five pound range for most of my adult life.
Caduceus wrote: Fri May 13, 2022 11:25 pm Is "body fat" very different from "visual fat"? As in, is it possible for someone to look fat but have low body fat, or for someone to be skinny and have high body fat? If not, then wouldn't looking in the mirror be good enough as an approximation?
It's definitely possible for someone to look skinny with too much fat - think thin, soft, no muscle tone. Less likely the other way, but you can have people who are heavier but metabolically healthy (but not everyone is The Rock.)
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