How does my digital scale determine “body fat” percentage? I’m assuming it’s some sort of electrical resistance? And how accurate is it likely to be, versus the old-fashioned (and painful!) caliper method?
I can’t answer your question, but I can share with you a quote from my freshman Phys Ed professor, who said of the calipers, “If it hurts, you’re doing it wrong.”
BTW, the most accurate measurement is obtained by weighing the subject in a pool of water.
Ask the people who probably made it:
I have one and I would say it is pretty close to useless. It requires you to input your gender, height, and if you are atheletic (y/n). This leads me to believe there is a fair amount of guestimation going on. It measures something for sure, but I don’t think it means much. I normally read from 18-21%. But if Ive been drinking, it reads much lower (15-16%). It also reads much higher if I am holding something heavy. I would say it’s little more than a glorified BMI chart.
Yep, I’d say my Tanita is pretty close to useless for the body fat measurement. I’ve checked the weight reading with a medical scale and that part is accurate enough, but the body fat readings have actually gone up as I lost lots of weight. A few years back when I was first getting back in shape, I went from over 89 kg to a low of 76 kg. That means I lost close to 30 lbs. of gross weight, and had gained a substantial amount of muscle, so I’d lost more than 30 lbs. of fat. The scale went from a reading of about 26% body fat to saying that I was at 24% body fat. The reading fluctuates by over 1% from hydration alone!
I only ever look at the “body fat” reading now for curiosity’s sake. I’m at 77 kg now, and can do all the major lifts (bench, clean and jerk, deadlift) with more than my body weight — a fraction under 2xBW on the deadlift — run a 5 k in 21–22 minutes, do 20 pull ups without stopping, and can see ribs and abs, though I’m not at washboard ripped levels yet. The Tanita says I’ve got 21% body fat. Ha. I’ll trust eyes and performance levels over that wild-assed guess of a figure any day.
Have you toggled the thing over to “athletic” mode? That may be all that’s needed to get better measurements.
I forgot to say yesterday…
These scales are OK for guesstimating and getting trends. If you want truly accurate figures, you need to either do a DEXA scan or full-body immersion. (Good luck on getting yuor health insurance to pay for either of these.)
My doctor rates these things as about as accurate and useful as those automatic blood pressure cuffs sold at the drug store - decent for screening and seeing trends, but you can’t put much faith into any one reading.
I have one and it was pretty far off. I know because I had a body fat calculation done with a “bod pod” and it differed by 17%. I took those readings and adjusted the height entry on my scale until it matched what the pod said I had. Now I have some trust in it.
BUT, how does my bone mass keep going up and down?