10% difference in BF% results?

Acg67

I don't care about my scale weight. I'm aiming to lose fat and not scale weight. Fat loss and scale weight loss aren't the same thing. I focus on my body fat percentage, pounds of fat and inches loss. I use my body fat scale and body fat handheld monitor to track my body fat percentage and I use this formula each month to see how much fat I'm losing.

Weight x Body fat percentage = Pounds of fat
Weight - Pounds of fat = Pounds of lean body mass

You always hark back to this formula, which does indeed work, however you are ignoring that is heavily dependent on the variable of bodyfat%, so to actually determine if you are losing fat, you have to use the most accurate form of bodyfat testing to determine bf% or else the formula is useless

CaptainGordo

I have haters and they love to try to come and attack me and make people believe that I don't know what I'm talking about.

Differences of opinion do not equate with hate. Also, repudiating opinions with facts is not hating. Let's not take things personally.

It's in the best interest of the community to share and analyze facts, and not anecdotal evidence and long-held myths.

MFPfriend

ROFL. I never spotted that. I guess I've never felt the need to ignore anyone before...

I think you'll find that I'm universally regarded as a lover, not a fighter. I don't hate you. I do find you tremendously perplexing.

I'm also intrigued that you always duck the 'how's your weight loss going' question...

It's a new feature, no worries.

CaptainGordo

I don't care about my scale weight. I'm aiming to lose fat and not scale weight. Fat loss and scale weight loss aren't the same thing. I focus on my body fat percentage, pounds of fat and inches loss. I use my body fat scale and body fat handheld monitor to track my body fat percentage and I use this formula each month to see how much fat I'm losing.

Weight x Body fat percentage = Pounds of fat
Weight - Pounds of fat = Pounds of lean body mass

You always hark back to this formula, which does indeed work, however you are ignoring that is heavily dependent on the variable of bodyfat%, so to actually determine if you are losing fat, you have to use the most accurate form of bodyfat testing to determine bf% or else the formula is useless

Exactly. Example...

Person weighs 140 lbs. Instrument A says 15% BF, while instrument B says 20% BF.

Calculation with Instrument A's Measurement
Weight (140) x Body fat percentage (15%) = Pounds of fat (21 lbs)
Weight (140) - Pounds of fat (21) = Pounds of lean body mass (119 lbs)

Calculation with Instrument B's Measurement
Weight (140) x Body fat percentage (20%) = Pounds of fat (28 lbs)
Weight (140) - Pounds of fat (28) = Pounds of lean body mass (112 lbs)

If the data you are using is inaccurate, the formula will produce inaccurate results. Garbage in, garbage out.

rileysowner

To those who have looked at the research on this, how does the BodPod match up to the better forms of measuring BF%?

http://weightology.net/weightologyweekly/?page_id=175

Bodpod v DEXA

Thanks. I can save the money I would have spent for a test using one.

CaptainGordo

Use can also use the ignore button.

I tried this, and the thread was much more boring.

rileysowner

Use can also use the ignore button.

I tried this, and the thread was much more boring.

But it makes me want to bang my head against a wall much less. Much better for my BP.

kimibunny

How people can go on for 3 pages arguing with someone stubborn is beyond me ...

At the OP, we have basically the same stats and 15% isn't even close to my body fat %. Unless you're secretly hiding some major guns, I'd say go and get the measurements redone by someone more experienced.

HMonsterX

I have haters and they love to try to come and attack me and make people believe that I don't know what I'm talking about.

Well...

...you don't know, that's the whole point! You have your own set ways, which is fair enough, it's up to you how you do this. But you keep trying to put what you do over as fact, when several people have disproved it. If you want to keep believing in what you do, despite overwhelming scientific evidence, go ahead, but you can't keep telling people that they are wrong, and your way is fact, when it clearly isn't.


...why am i thinking about religion right now? = /

steffiejoe

I'm so happy we have an ignore button!!:grumble:

OP I weigh 140.8 pounds and i'm 5'6 1/2. My BF is 26.5%.

My goal weight is 135 with 20%BF. I have a lot of work ahead of me.

AZackery

Well...

...you don't know, that's the whole point! You have your own set ways, which is fair enough, it's up to you how you do this. But you keep trying to put what you do over as fact, when several people have disproved it. If you want to keep believing in what you do, despite overwhelming scientific evidence, go ahead, but you can't keep telling people that they are wrong, and your way is fact, when it clearly isn't.


...why am i thinking about religion right now? = /

I will continue to use my body fat scale and body fat handheld monitor. As for religion, we can go to the bible. My message is open. If you want to talk religion, message me.

CaptainGordo

As for religion, we can go to the bible. My message is open. If you want to talk religion, message me.

Sidesteal

I tried this, and the thread was much more boring.

I'm crackin' up

HMonsterX

Well...

...you don't know, that's the whole point! You have your own set ways, which is fair enough, it's up to you how you do this. But you keep trying to put what you do over as fact, when several people have disproved it. If you want to keep believing in what you do, despite overwhelming scientific evidence, go ahead, but you can't keep telling people that they are wrong, and your way is fact, when it clearly isn't.


...why am i thinking about religion right now? = /

I will continue to use my body fat scale and body fat handheld monitor. As for religion, we can go to the bible. My message is open. If you want to talk religion, message me.

If you wont see the truth when we have solid, hard evidence in this thread, what's the point of having a religious debate? Everything i say will be countered with "I just KNOW there's a god"...

Anyway, back on topic!

AZackery

If you wont see the truth when we have solid, hard evidence in this thread, what's the point of having a religious debate? Everything i say will be countered with "I just KNOW there's a god"...

Anyway, back on topic!

You the one that brought up religion.

Why are people mad at me, because I'm using a body fat scale and handheld monitor?

meerkat70

What does the bible say about body fat measurement?

RonSwanson66

I will continue to use my body fat scale and body fat handheld monitor. As for religion, we can go to the bible. My message is open. If you want to talk religion, message me.

rileysowner

Yes time to abandon thread.

CaptainGordo

Why are people mad at me, because I'm using a body fat scale and handheld monitor?

Who's mad?

Folks are just refuting your opinion that science is inconsequential in regard to what the most accurate method of body fat measurement is. :flowerforyou:

meerkat70

You the one that brought up religion.

You know, he really didn't. He was drawing an analogy...

redheadmommy

Folks are just refuting your opinion that science is inconsequential in regard to what the most accurate method of body fat measurement is. :flowerforyou:

I do not think that she ever stated that the scale /handheld BF machines are the most accurate method to measure bodyfat. However it is a cheap and easily available method to gives you a rough estimate.

Getting a regular DEXA scan is just not a viable / affordable option for most people.
I am very surprised that here everybody have access to get such an accurate measure on a regular basis. Good for you guys! I only had a chance to get a BOD POD measure once , and I do not think that DEXA scan measure available in my city at all. Since these two most accurate methods are not accessible what is left? Water, caliper and handheld. Water measure is complicated and availability somewhat limited. Caliper is not better than handheld, so what is wrong to use handheld as a rough measure of progress?

AZackery

Folks are just refuting your opinion that science is inconsequential in regard to what the most accurate method of body fat measurement is. :flowerforyou:

I do not think that she ever stated that the scale /handheld BF machines are the most accurate method to measure bodyfat. However it is a cheap and easily available method to gives you a rough estimate.

Getting a regular DEXA scan is just not a viable / affordable option for most people.
I am very surprised that here everybody have access to get such an accurate measure on a regular basis. Good for you guys! I only had a chance to get a BOD POD measure once , and I do not think that DEXA scan measure available in my city at all. Since these two most accurate methods are not accessible what is left? Water, caliper and handheld. Water measure is complicated and availability somewhat limited. Caliper is not better than handheld, so what is wrong to use handheld as a rough measure of progress?

Thank you Redheadmommy.

CaptainGordo

Folks are just refuting your opinion that science is inconsequential in regard to what the most accurate method of body fat measurement is. :flowerforyou:

I do not think that she ever stated that the scale /handheld BF machines are the most accurate method to measure bodyfat.

* Underlining added for emphasis.

I'm not stuck on science.

taso42

Sweet, a new AZackery thread!

CBranson0503

I will continue to use my body fat scale and body fat handheld monitor. As for religion, we can go to the bible. My message is open. If you want to talk religion, message me.

ron swanson I love you.

Acg67

I do not think that she ever stated that the scale /handheld BF machines are the most accurate method to measure bodyfat. However it is a cheap and easily available method to gives you a rough estimate.

Getting a regular DEXA scan is just not a viable / affordable option for most people.
I am very surprised that here everybody have access to get such an accurate measure on a regular basis. Good for you guys! I only had a chance to get a BOD POD measure once , and I do not think that DEXA scan measure available in my city at all. Since these two most accurate methods are not accessible what is left? Water, caliper and handheld. Water measure is complicated and availability somewhat limited. Caliper is not better than handheld, so what is wrong to use handheld as a rough measure of progress?

i'm guessing you failed to read any of the studies or links provided in this thread? Also depending on the skill and experience of the tester, calipers are much better then BIA. And BIA barely beats BMI in terms of accuracy of bodyfat testing

and google is your friend

http://www.akama.com/company/Body_Composition_Clinic_Inc_a7cf02307757.html

http://www.behaviouralmedlab.ualberta.ca/en/AbouttheLaboratory/BodyCompositionTesting.aspx

AZackery

Facts about DEXA scan tests: http://exercise.about.com/cs/weightloss/a/bodyfat.htm

DEXA (dual energy X-ray absorptiometry)

This test is used to measure bone density, but it also measures body fat percentage as well as where most of your fat is (as if you didn't know). The facts about DEXA:
DEXA uses a whole body scanner and two different low-dose x-rays to read bone mass and soft tissue mass.
It takes about 10-20 minutes to do a body scan
It provides a high degree of precision with a 2-3 % margin of error.
This is considered a gold standard for measuring body fat and bone density
It's painless

Check with your doctor to see if this is right for you and call your insurance company as they may cover it. The cost is usually about $100.

Facts about Dunk tests/Hydrostatic Weighing: http://exercise.about.com/cs/weightloss/a/bodyfat.htm

Hydrostatic Weighing

This is just a fancy way of saying underwater weighing. Like DEXA, this test is one of the more accurate ones. How it works:
You sit on a scale inside a tank of water and blow out as much air as you can
You are dunked underwater, where you blow out even more air
Since fat is lighter than water, the more fat you have, the more you'll float. The scale measures underwater weight to figure out body density.
The margin of error is around 2-3%, but the accuracy depends on the amount of air you expel. You have to blow it ALL out or it won't be as accurate.
This is a difficult way to measure body fat since it can be uncomfortable and even scary to be dunked underwater with no air in the old lungs.

Many universities offer this test for around $25-$50. Call your local university and ask if they offer this. Fitness Wave offers mobile hydrostatic weighing in Southern California, Nevada and Arizona for $49.95.

Facts about body fat scales and handheld monitors: http://exercise.about.com/cs/weightloss/a/bodyfat_2.htm

Bioelectrical Impedance

This is one of the quickest methods of testing body fat using a BIA scale.
Either using a handheld scale or standing on a BIA scale, a signal passes either from hand to hand or foot to foot.
The faster the signal travels, the more muscle you have.
The results are based on the fact that water conducts electricity. Fat contains almost no water while muscle is about 70% water.
This method CAN be accurate (4% margin of error) but the results are affected by hydration, food intake and skin temperature. If you're dehydrated, you're body fat percentage will read higher than it is.

This is an easy way to test your body fat. Be sure you test at the same time of day, preferably first thing in the morning before breakfast, but after a glass of water.

All devices have errors. A person should trust the one that they are comfortable with. I trust my body fat scale and handheld monitor. I get the same readings from both.

CaptainGordo

DEXA: ...It provides a high degree of precision with a 2-3 % margin of error.

Dunk tests/Hydrostatic Weighing: ...The margin of error is around 2-3%...

Bioelectrical Impedance: ...This method CAN be accurate (4% margin of error) but the results are affected by hydration, food intake and skin temperature. If you're dehydrated, you're body fat percentage will read higher than it is...

All devices have errors.

Yes, they all have a margin of error, but some are more accurate than others. This is what the OP was asking, right? Why the differences? Well, as we can see, BIA is less accurate and can be affected by a number of factors.

A person should trust the one that they are comfortable with.

I'd be comfortable with one that told me I had 5% body fat, but it would be more beneficial to have an accurate reading.

I trust my body fat scale and handheld monitor. I get the same readings from both.

Both of them use Bioelectrical Impedance, so that would not be surprising.

redheadmommy

I do not think that she ever stated that the scale /handheld BF machines are the most accurate method to measure bodyfat. However it is a cheap and easily available method to gives you a rough estimate.

Getting a regular DEXA scan is just not a viable / affordable option for most people.
I am very surprised that here everybody have access to get such an accurate measure on a regular basis. Good for you guys! I only had a chance to get a BOD POD measure once , and I do not think that DEXA scan measure available in my city at all. Since these two most accurate methods are not accessible what is left? Water, caliper and handheld. Water measure is complicated and availability somewhat limited. Caliper is not better than handheld, so what is wrong to use handheld as a rough measure of progress?

i'm guessing you failed to read any of the studies or links provided in this thread? Also depending on the skill and experience of the tester, calipers are much better then BIA. And BIA barely beats BMI in terms of accuracy of bodyfat testing

and google is your friend

http://www.akama.com/company/Body_Composition_Clinic_Inc_a7cf02307757.html

http://www.behaviouralmedlab.ualberta.ca/en/AbouttheLaboratory/BodyCompositionTesting.aspx

I get it , caliper CAN BE better then handheld, IF the person is very experience and really know what she/he is doing. However if that is not the case , then it is really bad.
BTW, Thanks for the link . I didn't know the U of A has a Dexa scan now. I got my BOD POD measure at the exact same lab last year. However it is a research lab, it is not available for the general public. You have to participate in their research in order to get a measure. I definitely will look it up. Maybe I will qualify to be a research participants and then I may get a scan. YAY

RonSwanson66

From the Kreiger article:

1. Always remember that any number you get from a body fat test is a VERY rough estimate, and could be significantly off. Thus, don’t put too much faith in the specific number.

2 Point #1 holds true even when measuring change over time. I’ve heard many people say things like, “I lost 4 pounds of fat and gained 1 pound of lean muscle.” The numbers are never even close to being this precise. Given the error rate for measuring change over time, there’s a good chance those numbers are way off.

3. Even the best techniques have a 4-5% error rate when measuring change over time. This means, to accurately detect a decrease in body fat in most people, the body fat percentage needs to drop by a minimum of 4-5%. This means you should take long periods of time between measurements. I would say a bare minimum of 3 months, but 6 months is probably better. I see too many people taking measurements as often as every 4 weeks or so. That’s too frequent and unreliable.

4 Remember that fat-free mass and muscle are not the same thing. So just because your fat-free mass increases, doesn’t mean you had an increase in muscle.

5 You don’t need to have your body fat tested. A combination of body weight and circumference measurements (like waist circumference) will give you a very good gauge of whether you’re losing body fat. If your circumference measurements are decreasing, you are likely losing fat.

6 If you are going to try to track change in body fat over time, then I recommend hydrostatic weighing or skinfolds. These methods have shown the best accuracy rates for measuring change over time. However, these techniques are difficult to do with extremely obese people. For extremely obese people, I recommend simple body weight and circumference measurements.

7 When using skinfolds to track change over time, you don’t even need to bother calculating a body fat percentage. If the sum of your total skinfolds is decreasing, then you are likely losing body fat.

8 Whatever technique you choose, keep the conditions as identical as possible between measurements. That means having the same technician perform the measurement on you, using the same equipment, and at the same time of day.


Pay close attention to number 5. A scale and tape measure are all you need to track progress.