These "high dollar" tanita scales...

[RottenWillow]

its heavily dependant on electrolyte levels

can you expound on that? When electrolytes are depleted will it indicate a significantly higher bf percentage due to increased impedence?

 

[BUBBLES]

my tania scales says i am 32% fat when i know i am not, it is tatally way off the mark, and after a workout it says i am 28% fat...its weird...how can i drop 4% of fat within 3 hours??

they are not totally accurate...

 

[The Shadow]

can you expound on that? When electrolytes are depleted will it indicate a significantly higher bf percentage due to increased impedence?

DING DING!!!!

To make a valid measurement using bioelectrical impedance, the body must be in a stable condition; i.e. the amount of hydration (i.e. the amount of water in the body) and the amount of electrolytes must be consistent every time a measurement is made.
Why? Because bioelectrical impedance does not measure body fat, it measures the body's resistance to electrical current flow. Thus, for example, if the person is perspiring, the test results of the predicted body fat will be incorrect. In fact, in order to obtain accurate measurements, the National Institutes of Health (NIH) insists that the person being tested with bioelectrical impedance have fasted (no food, no drink) for a minimum of four hours, and preferably six hours.

Similarly, the body's water must be predictable, therefore, the person must void within one half hour prior to the test. If the person doesn't, the test is invalid.

Similarly, women prior and during the monthly periods tend to store water in the body, thus bioelectrical impedance - - - including the Tanita unit - - - cannot be used during that three to seven days.

^^from another site

 

[ashley2212]

Yeah, mine has male/female, height & athlete/normal too....... still told me 34% -- first thing in the am too.....

Yeah, I got about the same when I put myself in as "normal"... did she put you in as an athlete or "normal"? I would go back and try it as an athlete just for the hell of it... it will probably be more accurate...

I've also noticed, as Shadow said, it varies a lot. I've measured myself same time of day, same weight, same everything, and had it be 2% off from the previous time. It's not as accurate as it should be, but it's probably more accurate than a retard with calipers

 

[Sassy69]

Shit. Well I'm planning on getting the measurement done tonite at the gym. No way I'll be in the throws of a 4 hr fast prior to this. I was really not happy when I found this out last nite. I"m like SHOW ME THE CALIPERS LAZY ASS! Plus no one wants to see a potentially higher BF number & then sit there and wonder just how "off" it is -- what's the point, besides either pissing me off or making me depressed.

Hell.

 

[ashley2212]

Shit. Well I'm planning on getting the measurement done tonite at the gym. No way I'll be in the throws of a 4 hr fast prior to this. I was really not happy when I found this out last nite. I"m like SHOW ME THE CALIPERS LAZY ASS! Plus no one wants to see a potentially higher BF number & then sit there and wonder just how "off" it is -- what's the point, besides either pissing me off or making me depressed.

Hell.

If you can convince her to measure you on the scale and with calipers, I'd do that. At least that way, you have a general idea... it's either that or JUMP IN THE GIANT BUCKET O' WATER, LADY!!!

Given the options, I'd rather have someone pinch me and hook me up to machines and give me a general reading than do hydrostatic weighing... that totally freaks me out

Oh, by the way, when I had my bf% done with calipers, the woman told me that they have a device at the other gym she works at which is unbelieveably accurate. Apparently, this is the newest machine to measure bf% and they use it in the military. There are three little round stickies (like at the doctor's) that they stick on your forearm and bicep. I guess there's something about your arms that makes it more accurate to measure your bodyfat there than anywhere else... maybe the ratio between fat and muscle is more accurate in the upper body? I don't know, I wish I had asked more questions about that in particular... I'm going to try to do some research on it... let me know if you all know any info about that, I'd be interested to know the particulars on that.

 

[RottenWillow]

To make a valid measurement using bioelectrical impedance, the body must be in a stable condition; i.e. the amount of hydration (i.e. the amount of water in the body) and the amount of electrolytes must be consistent every time a measurement is made.

I knew about the hydration factor already but the electrolyte level is news, but makes perfect sense.

for those who dont know already, water is not a conductor (of electricity), as commonly believed. If for example you were in a jacuzzi filled with distilled water and someone threw in a live electrical wire you wouldnt get shocked. But if the tub were filled with tap water, which contains minerals, you'd get blasted.

 

[The_Monster]

As you get more and more muscle, they are less and less able to accuratly gauge youre BF level.
In my avatar its kind of little and not full body, but youll get the point, I was I think 258lbs (this was years ago). I was calipered at 13%... I questioned that, but my abs were smooth and I take lean readings everywhere but abdominal and I hold a bit of water subscapular, so I figured ok.
My Tanita scale said I was 20% (the same day)
Thats a BIG discrepency!

Now Im 307lbs and I caliper at 16%~17% (hey, its winter! ). I just put fresh batteries in the 'ole Tanita and was told 42%...

So I guess that makes me about 170lbs lean? Shit, my head weights 50lbs (I have a big ass head! lol)...

Ive talked in the past to some of the superheavies I used to train with and they had the same experiance.
One guy showed 13% the day of his show, and he was lean AND dry.

So like always, I would say to toss that S.O.B. out and put your trust in the mirror. Or email nude pictures of yourself to me for an "honest" evaluation!

 

[The_Monster]

Or email nude pictures of yourself to me for an "honest" evaluation!

Pretty Please?

 

[The Shadow]

nothing beats an expericneced technician and a pinch test.


I do mine at home....

3 site......