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Body Fat Measurement

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Hope this is a good place to post this topic. I didn't see a better place than Nutrition to post. Mike, once again, let me know if there is a better place and feel free to move this.

I have great frustration with measuring my body fat percentage. I have one of those scales that uses impedance to measure body fat, but I know these are notoriously inaccurate. Mine seems to give me a higher % in the morning vs in the evening, which sounds backwards to me. I have also had it range a full 4% from morning to evening. I do have some calipers, however, but I get frustrated with them too, because it seems the method of pinching folds can be so subjective. I've had some broad ranges of measurements with the calipers as well. I must be pinching differently each time. It has one of those electronic screens on it, and the stupid thing appears to be broken now.

So I guess I'm going to get another one. Anyone have any good experiences here? Maybe some better methods?

I'll bet Mr. FerrousMaverick has some good input :)

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I'll bet Mr. FerrousMaverick has some good input :)

I'll see what I can do. I'm in the same boat of being frustrated with body fat measurement. At the end of the day, unless you are willing to pay big bucks you are going to have to deal with some inaccuracy. What's more important however, is consistency. And as you've noted, the bio-impedance scales are terrible at that.

So, first understand how bio-impedance works. The general principle is that fat (an insulator) provides more resistance than muscle (which has a good amount of water in it). These scales use one of a few different algorithms to turn that resistance value into a body fat percentage. It also assumes that anything that is not fat must be lean body weight (or muscle). That includes the undigested food still in your digestive system. We tend to retain more water at the end of the day, so that is enough to throw off a bio-impedance scale by as much as 5%.

Calipers can be more accurate, but as you've also noted any inconsistency of the sample site and caliper pressure can cause measurement errors. The Accu-Measure Body Fat Calipers are set up to take away one of the sources of error: caliper pressure. Basically, you squeeze until the calipers snap into position, and you have an accurate pressure for that site. The best recommendation I saw for using calipers is to measure the precise location with a measuring tape and mark it with a pen. Yes, that means you will be wearing pen marks for a bit, but it's about the best way to make sure you have your measurement sites correct. As with all measurements, you need to have your muscles relaxed, so you might have to get someone else to help you. Finally, note that unless you have the seriously expensive medical calipers that doctors use, they become less accurate with age. Since the Accu-Measure calipers are only $20 USD, you might make that an annual purchase, or buy a bunch of them and break them out when you need to retire a set.

The only measurements that are more accurate are displacement tests or radiological tests, but those costs hundreds of dollars for each test. The two displacement tests are: water displacement and BOD POD (air displacement). You have to remain very still for both of these. Radiological tests are the only tests that actually measure body fat, but give you a healthy dose of radiation in the process. Pick your battles.

To get the most out of your body fat measurements the following keys will help you have usable results:

  • Be consistent: time of day, amount of clothing (for scales), measurement sites, etc.
  • Always measure before you work out. Your muscles stay tense a good long time after squats, that will throw off the calipers
  • Measure on an empty stomach. Not only does undigested food add to your total weight, it can even throw off the results for the displacement tests.
  • Treat the answer as a relative number. If you have a six pack you know you have around 10% body fat for men or 15% body fat for women. At that point just use your six pack as a guide for maintenance. If it's getting less visible you are increasing fat, but if it is becoming even more defined you are decreasing fat.

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Thanks, (I want to call you Maverick for some reason..what do you prefer?)

Maybe the undigested food is the culprit for my scales because my BF% is higher in the MORNING vs evening. With the scale, though, I have seen wild swings from day to day even though I am measuring at the same time with the same clothing. I'll give the Accu-Measure a try. The one that I have that's on the fritz is a FatTrack II. I believe it's suppose to keep the pressure constant too, but maybe I will have better luck with Accu-Measure.

Hmm...pretty sure I have a 4-pack :(

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Thanks, (I want to call you Maverick for some reason..what do you prefer?)

Maybe the undigested food is the culprit for my scales because my BF% is higher in the MORNING vs evening. With the scale, though, I have seen wild swings from day to day even though I am measuring at the same time with the same clothing. I'll give the Accu-Measure a try. The one that I have that's on the fritz is a FatTrack II. I believe it's suppose to keep the pressure constant too, but maybe I will have better luck with Accu-Measure.

Hmm...pretty sure I have a 4-pack :(

You can call me Maverick if you want, it's fine. I almost shortened it to the periodic symbol like FeMav, but then my brain parsed it as female so I figured I'd avoid confusion.

I think the bigger smoking gun for the scales is water retention. The more water you retain the more the scale thinks it's muscle. Due to salt intake we retain more water in the evenings than in the mornings--and day to day it also varies.

If you have a 4-pack then your BF% is somewhere between 10-15% which is very healthy (as a guy). I still have a keg that I'm working off. At least now it's a 1/4 keg hanging on the front and not the full keg surrounding my body. I'm currently about 20-21% and shrinking. Still on the high side for a guy, but if I were a girl I'd be pretty near 4-pack range.

The nice thing about the Accu-Measure is it's a simple mechanical solution. There's nothing much to go wrong. No motors, no sensors, no electronics. Just assume it starts getting inaccurate after a year of service.

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Since I've always been a skinny guy, body fat% hasn't been a big concern. I second the idea that any test/measurement should be used mainly to track if your BF is going up or down, not to get a number. I use the visible ab test to track my BF.

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I agree with Mike - I think unless you are someone who is trying to lose weight on this plan - I wouldn't overly concern yourself with BF - I certainly dont.

You can look at yourself on the scales in the morning and see whether or not you're carrying any fat.

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I agree with Mike - I think unless you are someone who is trying to lose weight on this plan - I wouldn't overly concern yourself with BF - I certainly dont.

You can look at yourself on the scales in the morning and see whether or not you're carrying any fat.

I still have about 20 lb or so to lose just to get a flat stomach. I can't do the "ab test" yet, so I do have to measure it from time to time. Because I have to be careful how much and what I eat, I need to make sure I'm not making things worse.

So far my scale has been giving me higher numbers for total body weight. Last BF measurement I lost 1.6%, not much but it's good to know that it is going in the right direction.

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Hope this is a good place to post this topic. I didn't see a better place than Nutrition to post. Mike, once again, let me know if there is a better place and feel free to move this.

I have great frustration with measuring my body fat percentage. I have one of those scales that uses impedance to measure body fat, but I know these are notoriously inaccurate. Mine seems to give me a higher % in the morning vs in the evening, which sounds backwards to me. I have also had it range a full 4% from morning to evening. I do have some calipers, however, but I get frustrated with them too, because it seems the method of pinching folds can be so subjective. I've had some broad ranges of measurements with the calipers as well. I must be pinching differently each time. It has one of those electronic screens on it, and the stupid thing appears to be broken now.

So I guess I'm going to get another one. Anyone have any good experiences here? Maybe some better methods?

I'll bet Mr. FerrousMaverick has some good input :)

Hi Stephen,

I don't think the bodyfat scales are too accurate to be honest. I get my bodyfat tested in the gym where they use the calipers and follow the Jackson & Pollock 7 site test. It's fairly accurate in terms of progress up or down but not sure whether you really can get an exactly correct figure. Best bet is to have the same person using the same calipers testing you all the time and then you'll get an indication of what way you are progressing. The guy who owns the gym recently did the Pollequin Biosignature course so I think all future tests will be done using this method which has 12 testing point sites. Apparently the thinking behind it is that spot reduction works and is based on different hormones in the body i.e. belly fat caused by cortisol, love handles caused by insulin, arm fat caused by estrogen etc and there are specific hormone supplements to target your problem areas (no doubt at great expense!). I haven't had the new test done but am curious to see the results. There are a few of the guys at the gym following the protocol and taking the supplements so it will be interesting to see their results over time..

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I get my bodyfat tested in the gym where they use the calipers and follow the Jackson & Pollock 7 site test. It's fairly accurate in terms of progress up or down but not sure whether you really can get an exactly correct figure. ... Apparently the thinking behind it is that spot reduction works and is based on different hormones in the body i.e. belly fat caused by cortisol, love handles caused by insulin, arm fat caused by estrogen etc and there are specific hormone supplements to target your problem areas (no doubt at great expense!). I haven't had the new test done but am curious to see the results. There are a few of the guys at the gym following the protocol and taking the supplements so it will be interesting to see their results over time..

I think Medhi hinted at there being studies that spot reduction is technically possible, but it doesn't work if you have over 20% body fat. I personally would be a bit hesitant to take supplemental hormones, and not for expense's sake. I'm currently down to just belly fat for the most part (yes, there's a little in other places but not that much in comparison) and lifting is helping to burn that up. Basically the stronger I get the quicker I burn those calories. That and some healthy eating with absolutely no carbs past dinner, giving me a good long time to burn fat. I figure that if I give it time, that belly fat will go away on its own as long as I'm continuing to eat sensibly.

The 7 site test and the 12 site tests are arguably going to give you less variance than the 3 site test--and that's a good thing any time you are trying to track body fat. The down side to those tests is that you absolutely have to have someone else do them for you. You can't get the caliper in the right place on your back, without someone else that has the eyes and the right leverage. Preferably someone trained and experienced, and you have the makings of a fairly accurate measuring system.

Just a couple links on food for thought (re. cortisol blockers):

Cortisol Blockers .com

Mayo Clinic on Cortisol Blockers

Basically, strength training is one of the best ways to burn that excess fat--assuming you aren't replenishing it faster than you can get it off.

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Hi Killian!

You're making me jealous of your gym again ;)

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For those who may want to use the multi-site caliper algorithms to calculate their body fat percentage, you can use the calculators on this site: http://www.linear-software.com/online.html

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I'm not inviting any opinion of "Four Hour Body" just yet, but Ferriss talks about the DEXA scan, which is apparently a highly accurate measure of BF%. Unfortunately in Canada there are only 3 cities that have it (Vancouver, Calgary and Toronto).

And it's only $100-$125 per scan.

I've only just encountered info about it today so I'm sure there's a lot more discussion going on about it.

Personally right now I'm just accumeasuring it. When it comes to the BF% metric, I think it's way more important that you track using the same method, than worrying about the accuracy. That said, if I had access to a DEXA right now in my chunky state, I'd definitely fess up the $250 bucks to get a scan now and in 6 months.

For someone just starting like me, with a higher BF%, I think the measuring tape and scale are going to say a lot more about my progress!

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For those who may want to use the multi-site caliper algorithms to calculate their body fat percentage, you can use the calculators on this site: http://www.linear-software.com/online.html

thanks for the link

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I've got a spreadsheet thing that calculates body fat percentage based on height, weight, and neck/waist/hip measurements. Probably not immensely accurate, but it's not a bad method of doing it I find.

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I wouldnt mind trying the method you use Beasley. I am having no luck with calipers (I'm sure if I saw it done or had someone to help me for the first 2 or 3 times I could get the hang of it.)

If any one is interested in the accumeasures Mav suggested I got mine for about $6 off of Amazon.

http://www.amazon.com/Accu-Measure-Fitness-3000-Personal-Tester/dp/B000G7YW74/ref=sr_1_1?ie=UTF8&qid=1313161979&sr=8-1

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Thanks for that link, Randy...very helpful. I have one of the electronic ones from Accumeasure, but it's been acting up. I just ordered the same one you got. Nice price, and simple :)

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The Navy formula is a good guide to use and cheap. I don't know how accurate it is... but if you want to monitor your lean gain progress on a constitent basis, all you need is a tape measure. Muscle Hack has a form to fill in if you don't want to crunch the numbers yourself.

I don't trust those scales. If you have ever played with an ohm meter to measure your resitance, it will flucuate with perspiration and other factors. I believe the scales use a similar method.

I am starting my 9th week of SL (plus modifications) and have so far gained 6lbs of lean and 5lbs overall. I have lost fat and gained muscle at the same time. I know this trend will end eventually. By monitoring weekly, I know when it will end and when to start making diet modifications. "Anything that is constantly monitored will be consantly managed." I stole that quote, I don't know from who.

The key is to use the same method to be consistent. Since the Navy formula is cheap, that is the method I stick to.

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The Navy formula is pretty inaccurate, but a little better than using BMI as a reference. All you need is a little extra water retention and bloating for any reason in your gut to throw that formula off. For very obese people, it can be more useful than calipers due to the problem of getting a consistent pinch at the measurement sites.

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The Navy formula is pretty inaccurate, but a little better than using BMI as a reference. All you need is a little extra water retention and bloating for any reason in your gut to throw that formula off. For very obese people, it can be more useful than calipers due to the problem of getting a consistent pinch at the measurement sites.

The BMI is something we should never use. It is only a reference for sedentary people. Even though the Navy formula has its problems with accuracy, if it is used consistently, you can see an overall trend with your results. Manage the trend, not the individual measurements.

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BMI was only meant as a reference point for its accuracy. As far as accuracy is concerned I'm lumping in consistency as well. Ab measurements can vary a lot--particularly if a guy forgets to cheat and suck their gut in. Not to mention, the variance in how tight the same person pulls the tape. All I'm saying is that it's no more accurate (trend wise or value wise) than the bio-electric measurement scales.

Take long term trends over short term trends. If you went up over the course of a week, but down over the course of a year, you are still heading in the right direction.

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BMI was only meant as a reference point for its accuracy. As far as accuracy is concerned I'm lumping in consistency as well. Ab measurements can vary a lot--particularly if a guy forgets to cheat and suck their gut in. Not to mention, the variance in how tight the same person pulls the tape. All I'm saying is that it's no more accurate (trend wise or value wise) than the bio-electric measurement scales.

Take long term trends over short term trends. If you went up over the course of a week, but down over the course of a year, you are still heading in the right direction.

Hey Mav,

Do you think that gains in your core/abs can throw off the Navy formula (Don't laugh)? I ask because visably I have lost a lot of gut fat, but my measurements have only decreased a little.

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It's possible. The Navy formula is based on the principle that as someone gets stronger their neck size gets larger. So two people with the same ab measurement (at the navel for men) the one with a larger neck would technically be rated at a lower body fat.

Now, when I was near 300lbs I had an 18" neck, and I think that would have given me a deflated body fat measurement. Now that I weigh a lot less, my neck also shrunk to about 16.5"--even with the muscle I've put on. So by the Navy standards my body fat would be inflated right now.

For me, the belly fat is the last to go, it's just the way I'm genetically disposed. The belly has gotten visibly smaller toward the top of the belly, but in the middle where you would take the measurements (both with calipers and with the Navy formula) hasn't changed appreciably. This is why the more caliper sites involved the potentially more accurate the final measure. We gain and lose fat in different places on our bodies at different rates.

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There's a body fat calculator on another site using waist/illiac/hip measurements. I'm new to the forum so I don't want to spam a link on the board, but I'd be more than happy to share it.

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There's a body fat calculator on another site using waist/illiac/hip measurements. I'm new to the forum so I don't want to spam a link on the board, but I'd be more than happy to share it.

Hey JB. My advice is to start a log on this site before sharing links, just so people take you seriously.

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