What do people think of those BMI/Fat % scales at the gyms

I did the one in the gym earlier this year, it said my BF was 40% which I knew couldn't be. The trainer tried to sell me $1000 package and tell me how I'm at risk for all these health problems. But even she says it seemed high from looking at me. I told her it was that TOM, she says that can skew the results. Think she would have asked that before she put me on that fancy scale. Apparently it is very dependent on how hydrated your body is, which means its not very reliable at all. I took my measurements and followed the YMCA formula and I'm 27%, a big difference from the 40% the gym said.

I think they are useful for showing change over time and change relative to overall weight. My weight has hardly budged in the past few months, but my BF is steadily dropping. I believe the scale, since my legs are firming up fast as I maintain 100 miles or more on my bike on a weekly basis, plus 12 or more miles of running/week.

I've had 3 bodyfat scales and a handheld Omron meter in the past 10+ years. They all show roughly the same #, so I can't imagine that any one of them has been too far off.

BTW, to the OP...my baby sister is named Nissa. Not a name I see every day. :happy:

Are you of Scandinavian descent with that name? My siblings and I all have Scandinavian names...I'm Kirsten and my brother is Grant.

I wonder if your scale is simply off. We had a Weight Watchers brand scale that went wonky after only 3 months, so we took it back to Target (I read bad reviews after we bought it, so I hung onto the receipt in case it went nuts...and it did). Or maybe the batteries need replacing...?

I'm not Scandinavian. My mom found the name in a baby book and she just liked it. But, she also pronounced it Neesa. So, my name is spelled Nissa, but sounds like Neesa.

My folks/sister have always pronounced it Nissa, shot i. My great grandmother was pronounced Keersten, but for some reason my folks wanted to "americanize" my name, so it's always been pronounced Kursten. In Scandinavia it's either Kjersten (j like y) or even Scheersten. I confuse people wherever I go!

I dont really think they work. The scales say my body fat is something like 46% but the instructor put me as 27% when he took all my measurements!

We were taught that bio-electric impedence BF measures (the scales with little metal plates for your bare feet) is the gold standard however, I believe this is simply for convenience being a fast and easy method for measuring an Average American's body composition (this is a huge problem).

Some of them simply rely on analog scales to measure BF and measures are greatly affected simply by what your inputs are - for instance, some models have you choose your activity as being an intense (practically marathon runner status) athlete with really high standards (600+min of INTENSE CARDIO - not weight lifting each week) or the alternative of being a typical sedentary American. Far from perfect...so I chose conservatively as being sedentary and was put at 15% BF back when I was at 180lbs (I'm 160-165 right now). This was a clinical scale being used

Using my personal scale (also bioelectric impedence), even at 160-165lbs, I am labeled at 17-18% BF. Do I really look the part?
<---Profile pic is current

I'm willing to bet the "dunk tank" is the most accurate, but least convenient. Calipers grossly underestimate BF. Proportion measurements (ones involving the neck, shoulders, waist, hips) seem to be fairly accurate...my measure put me around 7-8%. I believe these are commonly used by the millitary and navy because BMI is a joke to measure big/tall yet muscular guys who commonly fall into the overweight and obese categories

Caliper testing can be wrong. I've seen a youtube video where a trainer tested a woman's body fat percentage with a caliper and came out with 14% and there's no way that woman's body fat percentage was 14%. The woman was bottom heavy. I would trust a body fat scale, before I trust a caliper, after all, a scale shows my scale weight and if a scale can come up with a total for my pounds of fat + pounds of lean body mass, why can't a body fat scale give me a correct body fat percentage? A body fat scale and Omron handheld body fat monitor sends a signal that travels through the fat and that's how they come up with a percentage number. Calipers don't do that. Calipers can't even be used on very obese people or even people that have a 30% plus body fat percentage.

I know my body fat percentage and my measurements and for fun, I have used online body fat calculators to see what results they would give me and they had me at 25% /27% and I know that's false. I'm bottom heavy and I'm far from the 20's%..

In the video, how many places did they check? My trainer does it at 8 points around the body and averages the result. However I still don'trust it!

BTW, when you say you know yours, how did you find out?

We were taught that bio-electric impedence BF measures (the scales with little metal plates for your bare feet) is the gold standard however, I believe this is simply for convenience being a fast and easy method for measuring an Average American's body composition (this is a huge problem).

Some of them simply rely on analog scales to measure BF and measures are greatly affected simply by what your inputs are - for instance, some models have you choose your activity as being an intense (practically marathon runner status) athlete with really high standards (600+min of INTENSE CARDIO - not weight lifting each week) or the alternative of being a typical sedentary American. Far from perfect...so I chose conservatively as being sedentary and was put at 15% BF back when I was at 180lbs (I'm 160-165 right now). This was a clinical scale being used

Using my personal scale (also bioelectric impedence), even at 160-165lbs, I am labeled at 17-18% BF. Do I really look the part?
<---Profile pic is current

I'm willing to bet the "dunk tank" is the most accurate, but least convenient. Calipers grossly underestimate BF. Proportion measurements (ones involving the neck, shoulders, waist, hips) seem to be fairly accurate...my measure put me around 7-8%. I believe these are commonly used by the millitary and navy because BMI is a joke to measure big/tall yet muscular guys who commonly fall into the overweight and obese categories

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My thoughts exactly. The way I think of it is high and low end of a scale. So for me if set to athletic Im getting around 11% while on average i get around 16% so I figure im somewhere in between there. I use this and just looking at myself to estimate how much weight I'd like to loose. With my goal being 5% body fat I have about 15 lb's to loose still.

We were taught that bio-electric impedence BF measures (the scales with little metal plates for your bare feet) is the gold standard

Not even close.

BIA is the worst indicator of bodyfat %. BMI is a better predictor (and BMI sucks).




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