Body fat analyzer question

[luvtorun]

I used my BFA for the first time yesterday. Sarah told me that she had read that you take a female reading with your stats in and then a male reading with the stats in. Add these together, divide by 2 and substract 1.

It gave me a lower reading which we believe is probably more accurate.

Does anyone know the rationale behind this?

 

[Fit_mommy]

Interesting!! I did not know that and will have to try it tomorrow morning!!! My BF% seems way high to me! Maybe this formula will bring it closer to the truth! Thanks!

Sorry I can't answer your question though...

 

[luvtorun]

I got a lower reading Wendy. Sarah is going to check with someone she knows to see if they have the answer. If anybody on the forum knows, let us know.

 

[Fit_mommy]

I couldn't wait until tmrw morning so I did it today! I re-took my bf as a female and then switched it to male. (female reading was only 1/10% different from this morning) When I added the 2 #s, divided by 2 and subtracted 1, my % came out a full 3% lower!!!! How much lower did yours go?

 

[Imafitnessfreak]

This is all Ms. Fit's website offered but I am still trying:

Athletes

For those ladies who resistance train, it works best if you take a male and female reading and use that average, and take away 1%. For example, you are 130 pounds and you take a reading on the female setting and it reads 20.3%. Then, you take a reading using the male setting and it reads 16.1%. The average of the two is 18.2%. Subtract one percent and your body fat is 17%. With that, you know you have 22 pounds of fat and 108 pounds of muscle.

 

[Fit_mommy]

Thanks Sarah!!!

 

[luvtorun]

Wendy, mine came down 2.1%.

 

[Imafitnessfreak]

Hey Wendy, Don't forget about your implants. The bf analyzer sends a current through the body measuring the rate water is moving through the body. The more lean mass, the faster the water moves, the lower the bf reading. Correct me if I'm wrong but no water is going to move through those things! Makes sense that the Omron would read them as fat even though it's not. Lower your percentage for those!

 

[CathydsRNA]

I believe its electrical impedence that is measured not water flow. Water carries an electrical current and does not need to be moving. Since there is more resistance in fat, it takes the electrical impulse longer to move from the instrument, thru the body and back to the instrument where the measurement is made.

 

[Imafitnessfreak]

Cathy, I am sure you are right. Still, nothing is going to flow through an implant which leads me to believe it will register as fat mass.

 

[Kit_]

Actually if we are talking about breast implants with saline in them, the electric current will flow threw them, and since saline is only a bit denser then sea water, it shouldn't read it as fat, since fat will still float in it. As your body's natural impulses flow threw them all the time, if it didn't you'd have some server problems with your chest muscles. For example a lot of times a muscle spasm will create a low electric pulse in the body, if your pecs spazed, and hit that implant, if it blocks that means the electric pulse would bounce and your chest muscles would spaz again, creating a second electric pulse, and I'm sure you get the picture, you'd have dancing boobs. I know way too much about electric pulse in the body, due to having metal in my neck. I've been told its once of the worse places to ever have it.

Other implants like for knees/hips/etc that are solid, will report back much differently then breast implants, as well as the solid breast implants and the one's completely made of silicone.

Kit

 

[Imafitnessfreak]

Hi Kit, But how does the current even reach the saline part of the implant when the exterior is made of silicon? Wouldn't the current have to make it through the actual implant first before cruising through the saline fill of the implant?

 

[CathydsRNA]

Because the silicon material of implants as well as the other materials can carry an electrical current.

 

[CandiK]

Sarah is absolutely right about the male reading factoring resistance training. But, what I don't understand is why, if you are peri-menopausal or post-menopausal, the readings may be inaccurate??!! Or why you must take your reading right after you roll out of bed??!!

To me, all this factoring and estimating make me very leary about the results given by the Omron. JMHO.

 

[Fit_mommy]

As long as the # goes DOWN and not UP, I am happy happy happy! lol:7

 

[Mic]

I'm very late on this topic, but it sounds like a lot of you really like the Omron Bodyfat hand held device. Anyone compare this to the bodyfat scale and see what the difference is in numbers? I have the scale so I'm curious? Maybe I should get the Omron?

 

[Imafitnessfreak]

Mic, I'll let you know. I have the scale and a digital caliper. Once I get the Omron I'll let you know how it compares.

 

[Imafitnessfreak]

Also, costco.com seems to have the best price on the Omron. I am not a member so they added less than $2.00 to the total...still cheaper!

 

[CathydsRNA]

Hi Candi,
I agree. Electrical impedance measurement is still one of the least accurate methods of measuring body fat. Water immersion techniques are the most accurate and are the golden standard but are alas quite inconvenient. You are right about the factoring etc with electrical impedance. In addition, to the factoring you are doing after the measurement [(female plus male divided by two)minus 1], the machine is making calculations using on algorhythims that factor in your age, gender and activity level. It isn't a flat out measurement like water immersion and so that is the reason you fluctuate day to day...it is very inaccurate. Also fat % is not the only thing that can affect the reading...other tissues are more or less resistant to the current and that's why the algorhythims are used. The machine assumes men have more muscle and bone mass and this is factored in, that is why you get less BF% if you take the reading as a male. Ditto for the athlete mode. I had my BF% method measured underwater almost 2 yrs ago and had electrical impedance done at the same time. The electrical impedance was several % off (about 5% points off). The best thing that these things can be used for is too keep track of if you are losing or gaining BF but not as a measurement of what your exact BF% is. Also, you can't make much of a 1% loss or gain of BF as this is within the error of the readout.

 

[CathydsRNA]

Mic, I have an Omron and a scale. For my measuements, the scale shows a 4-5% higher reading than the handheld. This is because the scale is primarily reading lower body fat and the Omron is reading primarily upper body fat. Although the current theoretically can gothroughout the whole body before it comes back to the scale or handheld, much of it actually can come back to the scale/omron without having made a full circuit thru your entire body... it will take the path of least resistance back to the scale/omron. Those with both scale and handheld will add both measurements and divide by two to get a better estimate.