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# For people who talk of boyfat % a little bit of info Watch

1. There have been a few threads where people have mentioned their bf % after using the machines in places like boots and so.

Just to explain the flaws in this method a little to make sure you are not disappointed when the bros shoot you down.

Electronic Scales

How do they work?

Be they hand held or foot plate based they work on the same principle, a positive electrical current will be conducted from one of the foot/hand plates, the other will have a negative charge.

The current flows through the body from one plate to the other and records the time it took in nano seconds (1,000,000,000 nanoseconds: 1 second). The delay in time allows the internal computer to calculate he resistance in the body to electrical charge.

The calculation is based upon the fact that water conducts electricity. Fat contains almost no water while muscle mass is approx 70% water.

Warnings – They usually specify a 4% margin of error.

They are very quick and easy to use

The 4% error margin is the margin of error on their result; however their result is achieved in a fundamentally flawed way.

Electricity travels like water in the sense that it will take the route of least resistance from positive to negative much as water will on gradient. This means that it will only travel up one leg and down the other, or similarly the same principle for the arms. This bypasses the fattiest areas on humans (the midsection/chest & Back) and where it hits areas of large muscle and fat mass (such as the bum) the current can efficiently find a way to link muscle the muscle and avoid fat.

As such the 4% error is based upon a flawed principle in the first place.

Other problems are as it is using water, hydration, foot intake and skin temperature all affect the measurement, the more dehydrated you are the higher body fat % it will show all other conditions reaming the same.

When I can be arsed I will update this with some info on callipers, hydrostatic weighing (the most accurate method we have) and guess estimation.
2. Good info as always. I'm guessing height and leg length affects results as well.
3. I'm waiting on a cheap place to do a DEXA scan
4. but yeh, even calipers are flawed

so used for progress VS absolute BF%
5. c&p

Calipers (aka, the Pinch Test)
This method uses calipers to measure skinfold thickness at several areas of your body. How it works:

* An expert pinches your skin at different areas and measures them with calipers.

* The results are plugged into a formula to determine your body fat.

* The result is based on the idea that thickness of fat under the skin reflects total body fat.

* It CAN be as accurate as the methods mentioned about, but usually isn't. It depends on the skill of the tester at separating your fat from your muscle and finding the right spots to pinch.

* The results can also be skewed if you're older (since fat moves inward with age) or if you are nonwhite, since formulas are based on white subjects.

* This is one of the more accessible ways to check body fat and is generally painless.

You can get tested at most health clubs and universities for little or no cost. You can also buy your own calipers, but I wouldn't get too excited about the results you get. If you're not skilled at it, the results can be way off.Always make sure you get the same person to test your body fat since results can vary from tester to tester.
6. Fat also compresses and many calipers talk of multiple checks at one site for accuracy, this however does not work.
7. (Original post by Powerlifter)
Fat also compresses and many calipers talk of multiple checks at one site for accuracy, this however does not work.
would water levels affect readings? say if you are holding water in a certain area?

+ skin thickness, some have thinner skin than others so this can account for 1-2mm
would water levels affect readings? say if you are holding water in a certain area?

+ skin thickness, some have thinner skin than others so this can account for 1-2mm
Yes and yes, they are not that accurate, even hyrdo methods are only accurate to around 2-3% so the ******** that comes up with 10.4% or whatever of calipers is talking **** at best.
9. (Original post by Powerlifter)
Yes and yes, they are not that accurate, even hyrdo methods are only accurate to around 2-3% so the ******** that comes up with 10.4% or whatever of calipers is talking **** at best.
That and we can make the point that 'does it matter?'

in that, diff people look diff at even the same measured BF%

i like calipers, in that least they allow to see if a certain place is getting leaner
That and we can make the point that 'does it matter?'

in that, diff people look diff at even the same measured BF%

i like calipers, in that least they allow to see if a certain place is getting leaner
They are ok for a guide I suppose provided everything else was a constant e.g diet, time of day, fluid intake and so on blah blah
11. (Original post by Powerlifter)
They are ok for a guide I suppose provided everything else was a constant e.g diet, time of day, fluid intake and so on blah blah
I'd say there were the most accesible/easiest to measure progress in

in that, how often can you get a DEXA scan/hydro weigh?
I'd say there were the most accesible/easiest to measure progress in

in that, how often can you get a DEXA scan/hydro weigh?
If you train with weights I doubt you will ever need a Dexa scan at all.

I see no point in measuring it to be honest, Powerlifters/Strongment/Rugby Players etc work of athletic performance be it on the field or strength and bbuilders work off look, so who cares what bf% actuall is
13. Is there really no other way to find out? Surely several measurements around the body could do a similar job? Of course it wouldn't be accurate as hydro weighing or whatever it is?

For example I;m 6'1 and weigh 9 1/4 stone, which to be honest is pathetic, but surely this could be used to go some way towards estimating your body fat %?
14. (Original post by Luca118)
Is there really no other way to find out? Surely several measurements around the body could do a similar job? Of course it wouldn't be accurate as hydro weighing or whatever it is?

For example I;m 6'1 and weigh 9 1/4 stone, which to be honest is pathetic, but surely this could be used to go some way towards estimating your body fat %?
Not really, of the 9 1/4 stone how much is fluid, muscle, organs and so on
15. (Original post by Powerlifter)
Not really, of the 9 1/4 stone how much is fluid, muscle, organs and so on
Oh right never looked at it like that, sorry, thanks though.
16. (Original post by Luca118)
Is there really no other way to find out? Surely several measurements around the body could do a similar job? Of course it wouldn't be accurate as hydro weighing or whatever it is?

For example I;m 6'1 and weigh 9 1/4 stone, which to be honest is pathetic, but surely this could be used to go some way towards estimating your body fat %?
You weigh 57 KG and you're 6'1 ?
17. Meh, I've always seen bodyfat as a more supplementary tool than one that I would use as a testament of good health. Considering many of the portable ones can have atrocious margins of error coupled with the fact that bodybuilding depends largely on the look. Sometimes I check it just to give me an idea of where I am at prior to contest.
18. I'm 6'1 and a skinny runt at 85kg......are you sure you're not measuring yourself on kitchen scales or something?
19. Lol

I used one of those electric scales and it came up as like 23%... even though I'm about 12%
20. Pro endurance athletes tend to have mri/crt batteries to determine body fat iirc.

Updated: September 6, 2011
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