Bodyfat Testing

lvfunandfit

I'm having a "discussion" with a friend. How accurate are the body fat scales? I don't find them accurate. I know the Hydrostatic Body fat composition test is supposed to be the most accurate..... She seems to think the scale is more accurate than the skin fold test...I disagree.

What do you think?

SHBoss1673

I'm having a "discussion" with a friend. How accurate are the body fat scales? I don't find them accurate. I know the Hydrostatic Body fat composition test is supposed to be the most accurate..... She seems to think the scale is more accurate than the skin fold test...I disagree.

What do you think?

actually DEXA is the "gold standard" for body fat testing, but yeah, hydrostatic is very accurate, as is the "bod pod" (about 1.5% margin for error). Most of those bio electrical impedance scales are wildly inaccurate and depend greatly on your hydration level and the contact made.

If you live in the US, you should be able to find a Bod Pod location near you (google bod pod for the website) and they are relatively inexpensive (about 50 to 100 bucks for a scan).

MariSama44

I did alot of research before purchacing my handheld body fat analyzer. In terms of accuracy, from highest to lowest:

1. Hydrostatic
2. Bioelectrical Impedance Analysis
3. Calipers and skin folds

Now Bioelectrical Impedance Analysis or BIA for short is what those body fat scales do. However, this is a great and accurate alternative to the other two because its afordable enough to do regularly, and you can do it without assistance. But you should choose a handheld unit instead of a scale with body fat built in. why?

BIA works by conducting electrical signals through the subject's body. It takes into account your height (how far the electricity travels) and determines the fat content of your body by measuring the elecrtical resistance after it travels through your body. The problem with the scales is that the electrical signals travel through your legs. You know how your hands outstretched equals your height? Well its not always true in legs, so the distance the electricity travels varys with the height data you provide the machine, therefore botching the calculation. Not to mention, most of us carry alot of weight in our lower regions (esp. Women) and that may cause the scale to read higher than it should on your body fat percentage.

Invest in a hand held BIA device. Measuring through your arms is more accurate, especially if you read the instructions and are sure to only test your fat under ideal conditions, IE not after chugging a gallon of water, not after eating, not after exercising etc.

http://www.amazon.com/Omron-HBF-306-Body-Fat-Analyzer/dp/B00006WNPU

stroutman81

I did alot of research before purchacing my handheld body fat analyzer. In terms of accuracy, from highest to lowest:

1. Hydrostatic
2. Bioelectrical Impedance Analysis
3. Calipers and skin folds

Can you show me the research you read showing BIA to be more accurate than SF measurement, please?

MacMadame

The calipers can be very accurate or very inaccurate based on the skill of the measurer. But, if you have a lot of loose skin from losing a lot of weight, they will over-estimate your body fat even with a skilled measurer.

I find the scales to be good for monitoring trends. Mine varies by about 3% over the course of the week depending on when I've done strength training, how hydrated I am, etc. OTOH, when I wasn't working out much this winter due to injury, that range gradually crept up and, now that I'm back to almost full training, it's moved back down. During that same time period, my weight was relatively stable and did not accurately reflect what was going on with my fitness level the way the body fat % number did.

But my scale cost $300 and has contact points for the hands as well as the feet. My cheep-o scale that does body fat % is okay for following big trends but it's so far off in general that those trends have to be in the double-digits before they are noticeable.

MariSama44

In my opinion reading about the pros and cons I see that calipers lose accuracy over time. I was reading of course for myself, and really unless you have someone who has alot of experiences testing skin folds to perform it for you, accuracy gets lost when you perform it on yourself or ask someone who doesn't know what they're doing to give you a reading. I also know from personal experience, the readings I've gotten from calipers have varried more than my Omeron has.

elizamary77

I did alot of research before purchacing my handheld body fat analyzer. In terms of accuracy, from highest to lowest:

1. Hydrostatic
2. Bioelectrical Impedance Analysis
3. Calipers and skin folds

Now Bioelectrical Impedance Analysis or BIA for short is what those body fat scales do. However, this is a great and accurate alternative to the other two because its afordable enough to do regularly, and you can do it without assistance. But you should choose a handheld unit instead of a scale with body fat built in. why?

BIA works by conducting electrical signals through the subject's body. It takes into account your height (how far the electricity travels) and determines the fat content of your body by measuring the elecrtical resistance after it travels through your body. The problem with the scales is that the electrical signals travel through your legs. You know how your hands outstretched equals your height? Well its not always true in legs, so the distance the electricity travels varys with the height data you provide the machine, therefore botching the calculation. Not to mention, most of us carry alot of weight in our lower regions (esp. Women) and that may cause the scale to read higher than it should on your body fat percentage.

Invest in a hand held BIA device. Measuring through your arms is more accurate, especially if you read the instructions and are sure to only test your fat under ideal conditions, IE not after chugging a gallon of water, not after eating, not after exercising etc.

http://www.amazon.com/Omron-HBF-306-Body-Fat-Analyzer/dp/B00006WNPU

This is interesting I do am interested in where you did this research cause I bought the omron a while back and was mad at myself wishing I would have just gotten the Calipers cause I feel like its just giving me my bmi. so I have wondered about its accuracy. I have also read in other forums that the Omron is not accurate and does just give bmi. It would be great if your findings are true cause then I don’t have to spend more money and I didn’t waste money, but I’m kind of doubtful.

elizamary77

In my opinion reading about the pros and cons I see that calipers lose accuracy over time. I was reading of course for myself, and really unless you have someone who has alot of experiences testing skin folds to perform it for you, accuracy gets lost when you perform it on yourself or ask someone who doesn't know what they're doing to give you a reading. I also know from personal experience, the readings I've gotten from calipers have varried more than my Omeron has.

OK just to be clear your research is your own personal use of the Omron and the fact that it gives you similar or the same numbers when you used it?

MariSama44

This is interesting I do am interested in where you did this research cause I bought the omron a while back and was mad at myself wishing I would have just gotten the Calipers cause I feel like its just giving me my bmi. so I have wondered about its accuracy. I have also read in other forums that the Omron is not accurate and does just give bmi. It would be great if your findings are true cause then I don’t have to spend more money and I didn’t waste money, but I’m kind of doubtful.

My omeron gives a percentage. its located at the top of the LED screen and its pretty consistant when I take the measurement at the same time durring the day when I'm not stuffed with food. The BMI is displayed in the bottom which i disreguard. i havent heard of an omeron only showing BMI. it would seem dumb for it to only display a height/weight ratio calculation that can easily be found online and doesnt requare any BIA technology at all... Basicly I just Googled how you measure body fat percentage one day and read everything I could get my eyes on and then made judgement based off of that. Alot of people claim they're not accurate, but alot of the people that make that claim dont follow the instructions that's included in the manual to the analyzer.

elizamary77

This is interesting I do am interested in where you did this research cause I bought the omron a while back and was mad at myself wishing I would have just gotten the Calipers cause I feel like its just giving me my bmi. so I have wondered about its accuracy. I have also read in other forums that the Omron is not accurate and does just give bmi. It would be great if your findings are true cause then I don’t have to spend more money and I didn’t waste money, but I’m kind of doubtful.

My omeron gives a percentage. its located at the top of the LED screen and its pretty consistant when I take the measurement at the same time durring the day when I'm not stuffed with food. The BMI is displayed in the bottom which i disreguard. i havent heard of an omeron only showing BMI. it would seem dumb for it to only display a height/weight ratio calculation that can easily be found online and doesnt requare any BIA technology at all... Basicly I just Googled how you measure body fat percentage one day and read everything I could get my eyes on and then made judgement based off of that. Alot of people claim they're not accurate, but alot of the people that make that claim dont follow the instructions that's included in the manual to the analyzer.

I followed the instructions so if its accurate then cool, how far off is your bmi and fat%? are they fairly close?...How do you know the ppl making the claim that they're not actuate aren't following the instructions? did they say that lol. I would think if something wasn't working I should maybe go back and read up if I didn't already. I mean I even read all the directions on my new scale when I bought it and Im pretty sure I know how to stand sill on a square block. Also have you tried using it on at the times they say you shouldn't, ya know after eating and what not to see if your number changes? I think I'll try that and see what happens.

MariSama44

I already said my Body fat percentage goes down consistantly with my weight loss. For my lifestyle its the best and most accurate tool for my money and time. My BMI is always right and since I dont have hydrostatic/caliper tests as often as I can take it with my omeron, i dont know how "far off" it is, All I know is it stays similar and consistant and so I feel okay about saying its accurate. It doesnt say one day I'm 39% and the next tell me I'm 47%. It varies within a percent and goes down as I lose weight. Just like the scale in my bathroom does.

I made the claim that people are using it wrong becaues they are. they measure at times that aren't consistant and they eat and exercise before using it. The instructions say not to , and people who observe those guidelines tend to have more accurate readings. I read this stuff in comments on amazon that reviewers wright.

You will also notice that I said explicitly in my post that the measurements on scales is far less accurate than hand held BIA readings. and i explain why. I'm referring to a hand held BIA , and I'm also referring to the instruction manual that came with it that instructed me to follow guidelines whenever I measure to make sure its as accurate as it can be.

I've tried using it at the wrong times and my reading is higher. I read my measurement in the morning after I've woken up a little bit, and in the evenings 2 hours or more after dinner. I measure about 2-3 times a week at most, mostly keep up with a scale.

elizamary77

First I’m not attacking you I have the same Body fat reader. I just want to know if I can really trust it. Body fat% loss and weight loss are not hand in hand so just because it goes down along with you weight does not make it accurate, your BMI goes down along with your weight loss too and those are tied together. There are a lot of people that lose muscle when they are losing weight…and keep in mind that consistent doesn’t mean the same as accurate. I am only questioning you because I’m too want to know what is accurate like the OP. So I am sorry if I offended you by questioning you as it was not my intent.

MariSama44

Yes, I understand that body fat does not = weight. That's the whole reason I got a body fat measuring device. I up my protien and do weight training to counteract the burning of muscle, I'm aware. I am describing my own experiences. I still listed hydrostatic testing as the most accurate in my original post.

lvfunandfit

no bod pod near me. =(

I'll let you know how the skin fold test compares to my scale. my scale is fluctuating btwn 16-19%. We'll see how it goes.

Iceprincessk25

I find the scales with the body fat analyzer to be junk. I wouldn't waste my $$ on those. The skin fold calipers can be accurate but it depends on who is doing it. There's a LARGE margin for error with that. With that being said....I would pick the calipers over the scale with the body fat analyzer included on it.

Now I'm NOT talking about the large bioimpedence machines........we're talking everyday scale with the body fat analyzer on it.

That's too bad there isn't a Bod Pod near you. We're gonna get it done soon. It's only $35 and they give a discount for repeat testing. Should be interesting.

MacMadame

I've used the Omron at my gym and through a friend who does RMR testing and I don't find it accurate at all. Any device that only shoots the bio-impedence through two places is bound to be inaccurate. If it shoots it through your hands, it's going to give too much weight to your upper body, including your (full of fat) boobs. If it shoots it through your feet, it gives too much weight to the lower body.

chrisdavey

I have the accumeasure calipers and have been using them for about 12 months now. Basically, I don't really care what number it gives me just the mm. Obviously, if the mm are going down then that is a good thing :P Going by the accumeasure charts I believe that the %'s may be a little optimistic well for me anyway. I am apparently 9% by the calipers at 6mm. However, coincidentally a gym owner I know got the full testing done to his clients with 12 spots measured and his son is exactly the same height and weight as me but had overall larger legs and chest (this guy deadlifts 210kg at 73kg and I DL 135kg so I think that proves that he has more muscle mass than me :P) and he was at 11% by the test which would mean that I am higher than that.

I am going to grab one of these Omron ones and check it out. Cheap as chippies anyway

lvfunandfit

I find the scales with the body fat analyzer to be junk. I wouldn't waste my $$ on those. The skin fold calipers can be accurate but it depends on who is doing it. There's a LARGE margin for error with that. With that being said....I would pick the calipers over the scale with the body fat analyzer included on it.

Now I'm NOT talking about the large bioimpedence machines........we're talking everyday scale with the body fat analyzer on it.

That's too bad there isn't a Bod Pod near you. We're gonna get it done soon. It's only $35 and they give a discount for repeat testing. Should be interesting.

That is my argument....I don't think the scales are accurate. I use ours to gauge changes... but I know the numbers aren't correct. We only have this scale because it was on sale and our other scale broke. On my scale I've gone form 24% to 17%... so I know I've lost body fat. BUT, I don't know if the starting number was accurate and if my current number is anywhere close to being correct. That's where the conversation with my friend started. She felt it was accurate and we debated a bit. I want to do the Hydrostatic test, but for now I'll do the calipers just to check. I do think that is much more accurate than the scale. So, we'll see.... next I'll do the Hydrostatic test and if I can find a bod pod I'll for sure do that in the near future!

lilmissy2

I did alot of research before purchacing my handheld body fat analyzer. In terms of accuracy, from highest to lowest:

1. Hydrostatic
2. Bioelectrical Impedance Analysis
3. Calipers and skin folds

This is also what I have been taught BUT a true BIA (the one referred to in this list) is NOT those body fat measuring bathroom scales you can buy, it's a very high tech and expensive piece of equipment. The bathroom scale variety are often very inaccurate.

Skin folds can be very accurate or very inaccurate! They need to be done in exactly the right places by somebody professionally trained in anthropometry.

DEXA is vaguely familiar to me (I'm trying to remember 2nd year uni here!) but I think it's a more recent development so most books etc won't have it in the list.

PJilly

I have one of those scales, and it is ridiculously inaccurate. I've had two body comps done recently. One was ultrasound (not widely available), and my body fat was about 23 percent. That was a couple of weeks ago. This week, I had a hydrostatic (underwater) test, and my body fat was 21.5 percent. Guess what my Tanita scale says my body fat percentage is? 36.5 percent. :noway:

chrisdavey

Omron BIA tester just arrived. WIll update with some figures to see how they compare to accumeasure calipers when I can test property

Azdak

Methodology depends on the skill of the user and the type of body you use it on.

I don't ever discuss DEXA because it is out of the reach of most people.

For low to mid bodyfat levels, for many body types, and in the hands of an experienced operator, a 3-site skinfold test has been shown to be as accurate as hydrostatic weighing. It's not good for large people or (esp men) those with a lot of visceral fat. However, in the 5%-30% body fat range, other than the above exception, I have found it extremely accurate. But I have also done about 10,000 of them, so I feel pretty comfortable both doing the measurements and interpreting the results.

Unfortunately, most people I see these days are so overweight that calipers aren't very useful.

One advantage of calipers --as someone mentioned earlier--is that they provide actual measurements instead of interpretations of OTHER measurements. So, even if the BF% number is inaccurate, a reduction in the actual skinfold thicknesses is a more consistent indicator of reduced body fat. Bioimpedance scales can't make the same statement.

In my new job, we have a clinical Tanita scale--I think it is the 418 model--the one that has the foot platform and the hand sensors and measures 5 segments. At times I have been impressed with it's accuracy--it has exactly matched about 6 people I did with calipers as well. OTOH, on me, it overestimated my Lean Body Mass by about 33 pounds and underestimated by BF% by at least 5%. I have also seen some widely varying LBM numbers when re-assessing members and comparing current numbers with past readings. That's really frustrating because it is so much more difficult to do effective interpretations.

I looked at a lot of home models when I bought my last scale and ultimately decided that even the more expensive Ironman Tanita scales were too unreliable--so I just opted for a nice $30 strain-gauge digital and my trusty tape measure.

Hydrostatic weighing is nice, but it is not easy to do. There are also several factors (water temp, actual measurement of residual lung volume vs using a reference text, clothing worn, among others) that are not always easy to control and that, in the end, can significantly increase the standard of error. I personally do not think that hydrostatic weighing is a practical method for assessing large numbers of people.

mworld

to answer your basic question the skin fold test is going to be a bit more accurate if done 'properly'...but there's of course WAY more margin of error if she's clueless trying to do it herself.


either way...the real question is what's the point? all you need is some measurement to gauage 'progress' (hopefully) by/

lvfunandfit

Methodology depends on the skill of the user and the type of body you use it on.

I don't ever discuss DEXA because it is out of the reach of most people.

For low to mid bodyfat levels, for many body types, and in the hands of an experienced operator, a 3-site skinfold test has been shown to be as accurate as hydrostatic weighing. It's not good for large people or (esp men) those with a lot of visceral fat. However, in the 5%-30% body fat range, other than the above exception, I have found it extremely accurate. But I have also done about 10,000 of them, so I feel pretty comfortable both doing the measurements and interpreting the results.

Unfortunately, most people I see these days are so overweight that calipers aren't very useful.

One advantage of calipers --as someone mentioned earlier--is that they provide actual measurements instead of interpretations of OTHER measurements. So, even if the BF% number is inaccurate, a reduction in the actual skinfold thicknesses is a more consistent indicator of reduced body fat. Bioimpedance scales can't make the same statement.

In my new job, we have a clinical Tanita scale--I think it is the 418 model--the one that has the foot platform and the hand sensors and measures 5 segments. At times I have been impressed with it's accuracy--it has exactly matched about 6 people I did with calipers as well. OTOH, on me, it overestimated my Lean Body Mass by about 33 pounds and underestimated by BF% by at least 5%. I have also seen some widely varying LBM numbers when re-assessing members and comparing current numbers with past readings. That's really frustrating because it is so much more difficult to do effective interpretations.

I looked at a lot of home models when I bought my last scale and ultimately decided that even the more expensive Ironman Tanita scales were too unreliable--so I just opted for a nice $30 strain-gauge digital and my trusty tape measure.

Hydrostatic weighing is nice, but it is not easy to do. There are also several factors (water temp, actual measurement of residual lung volume vs using a reference text, clothing worn, among others) that are not always easy to control and that, in the end, can significantly increase the standard of error. I personally do not think that hydrostatic weighing is a practical method for assessing large numbers of people.

Thank you for this reply! Your posts are always very helpful.
My friend who is a trainer had to reschedule with me to test my BF%. So, hopefully I'll find out what her calipers say. She trains women for IFBB competitions. She's pretty precise with everything she does. We'll see though. . . I just want to have a gauge and see how I've improved.

MacMadame

Actually, there are now places that will do a DEXA scan on you for about the same price as the hydrastatic testing. I think it's the new "in thing" in fitness. :happy:

Iceprincessk25

Methodology depends on the skill of the user and the type of body you use it on.

I don't ever discuss DEXA because it is out of the reach of most people.

For low to mid bodyfat levels, for many body types, and in the hands of an experienced operator, a 3-site skinfold test has been shown to be as accurate as hydrostatic weighing. It's not good for large people or (esp men) those with a lot of visceral fat. However, in the 5%-30% body fat range, other than the above exception, I have found it extremely accurate. But I have also done about 10,000 of them, so I feel pretty comfortable both doing the measurements and interpreting the results.

Unfortunately, most people I see these days are so overweight that calipers aren't very useful.

One advantage of calipers --as someone mentioned earlier--is that they provide actual measurements instead of interpretations of OTHER measurements. So, even if the BF% number is inaccurate, a reduction in the actual skinfold thicknesses is a more consistent indicator of reduced body fat. Bioimpedance scales can't make the same statement.

In my new job, we have a clinical Tanita scale--I think it is the 418 model--the one that has the foot platform and the hand sensors and measures 5 segments. At times I have been impressed with it's accuracy--it has exactly matched about 6 people I did with calipers as well. OTOH, on me, it overestimated my Lean Body Mass by about 33 pounds and underestimated by BF% by at least 5%. I have also seen some widely varying LBM numbers when re-assessing members and comparing current numbers with past readings. That's really frustrating because it is so much more difficult to do effective interpretations.

I looked at a lot of home models when I bought my last scale and ultimately decided that even the more expensive Ironman Tanita scales were too unreliable--so I just opted for a nice $30 strain-gauge digital and my trusty tape measure.

Hydrostatic weighing is nice, but it is not easy to do. There are also several factors (water temp, actual measurement of residual lung volume vs using a reference text, clothing worn, among others) that are not always easy to control and that, in the end, can significantly increase the standard of error. I personally do not think that hydrostatic weighing is a practical method for assessing large numbers of people.

I absolutely agree about the hydrostatic weighing. Yes it's said to be the gold standard and blah blah blah......but has anyone ever had it done?? It SUCKS. It's impossible to blow out all the air they want you to and it's just a pain in the *kitten*.

SHBoss1673

I still feel like the Bod Pod is the best compromise. Does anyone have any experience with it? I'm thinking of going soon, just to see what it's like, I already know my BF% (approximately, it's been a while but my body hasn't changed a lot since I got it) but I'd like to be able to recommend or discourage the Bod Pod, and the only way I can do that is by trying it out.

From all my research it's supposed to be about the same accuracy as hydrostatic testing (about 1% margin for error). And you neither need to get wet, nor do you have to hold your breath. The bod pod uses Air Displacement Plethysmography to calculate body fat %. Essentially they take weight and volume of air, do a calculation to figure out specific density. I don't know all the details of the calculations, but the company is very receptive to questions, and open in their dissemination of research; that, more than anything else, tells me that they are on the up and up.

questionablemethods

I still feel like the Bod Pod is the best compromise. Does anyone have any experience with it? I'm thinking of going soon, just to see what it's like, I already know my BF% (approximately, it's been a while but my body hasn't changed a lot since I got it) but I'd like to be able to recommend or discourage the Bod Pod, and the only way I can do that is by trying it out.

From all my research it's supposed to be about the same accuracy as hydrostatic testing (about 1% margin for error). And you neither need to get wet, nor do you have to hold your breath. The bod pod uses Air Displacement Plethysmography to calculate body fat %. Essentially they take weight and volume of air, do a calculation to figure out specific density. I don't know all the details of the calculations, but the company is very receptive to questions, and open in their dissemination of research; that, more than anything else, tells me that they are on the up and up.

I've been looking into getting it done at the gym at my university. The cost isn't too much (around $50, if I recall). I would like to have a good idea of a goal weight to shoot that is based on an actual lean mass to fat ratio instead of "this number sounds good". I wouldn't be able to tell you the accuracy of the method, however, because I have no idea what my BF% is at the moment. Maybe I could get them to do caliper testing too and just see how well the two numbers match up.

MacMadame

.but has anyone ever had it done?? It SUCKS. It's impossible to blow out all the air they want you to and it's just a pain in the *kitten*.

Heh, I've done it and I thought it was fun!

But I also think biking 100 miles is fun so maybe my idea of fun isn't typical. :laugh:

I really want to get the DEXA scan done. I just had a chance to get the hydrostatic testing for $20 at a triathlon expo so I took it. But DEXA scans are $75-99 around here (and often the hydrostatic test is that much as well) and I just can't justify it.

I also want to get my RMR tested and my VO2 Max. I like numbers!

PJilly

Ha, I had it done last week, and I thought it was kind of fun too! I should go find a Bod Pod and do that so I can compare with my hydrostatic numbers.

lvfunandfit

well, it turned out I was a 17.9%! I'll take that for now! I'd like to be at 15-16%. I know it's not totally precise but the number made me happy!