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Return body fat scales, they call me obese sometimes and body fat goes down after a big bowel movement

14 replies

Rufusgy · 14/09/2015 10:44

Body fat scales are junk right?

I vary from 24% fat to 32% fat. I've just lowered my % by having a large bowel movement. Surely they can't be counting that as fat?

OP posts:
capsium · 14/09/2015 10:56

I can change my fat percentage reading on mine by saying I'm a man or very carefully placing my feet forward on the sensors so more of my foot covers them or by leaning on something to make my weight less.

I think the point is, is that they are a really approximate guide. They work by measuring how quickly an electrical current takes to travel through your body, since fat is more insulating than muscle but they seem to combine this reading with weight and information such as whether you are an adult or child, male or female.

One thing I will say is that my percentage did go down when I lost weight and that people of the same weight can show different fat percentage readings.

Spartans · 14/09/2015 11:49

Body fat scales are really inaccurate. I have the pinch test every two months instead. Not entirely accurate either but I find it is more so than scales. As pp said, they combine age, weight, the current etc. so it is an educated guess.

Rufusgy · 14/09/2015 12:22

I guess I was expecting more from them. It doesn't say anywhere that it is a rough estimation and with a digital display you kind of expect something accurate.

I was hoping they would show when I loose weight and gain muscle but that doesn't happen at all. I know I've lost fat but the reading is the same ish.

OP posts:
MaxieMouse · 14/09/2015 12:29

They are inaccurate but the readings shouldn't vary that much for no reason. 24 to 32 is a massive difference. I'd say there's something wrong with your scales. The only time I've seen such a difference in mine was when the kids changed my age to 96.

dontrunwithscissors · 14/09/2015 12:33

Mine is lower in the evening than in the morning (about 26% to 30%), but are otherwise fairly consistent.

SonjasSister · 14/09/2015 12:37

Mine are more consistent than that too. It's important to ensure hands and feet are dry - damp hands may up your muscle!. But yes re BMs, I always wait till I've 'gone' before using them ;)

Rufusgy · 14/09/2015 12:38

Tbh thats the biggest and not normal variation, they do vary by 4-5%, I had no idea standing on them differently affected it

OP posts:
choccyp1g · 14/09/2015 12:39

It does make sense to be higher % fat in the morning, as you lose water and therefore weight overnight, but the fat would be virtually unchanged.

capsium · 14/09/2015 12:59

Re. Standing on the scales, you get better contact (for the current) if your feet cover more of the contact area.

Re. Leaning on something (I did this for experimentation's sake), I concluded this just shows the weight reading does affect the fat rating.

The manual of my scales said water also aids conduction, so if you are dehydrated you might also get a higher fat reading.

MaxieMouse · 14/09/2015 13:22

Variation between morning and evening is normal, so is after a bath. Strangely enough I found that the values are higher when I'm coming down with a bug, even before I start feeling ill, and going back to normal when I'm recovered - I don't know what that is all about but it's uncanny.

Tirinen · 14/09/2015 14:27

The scales use an electrical current and measure the resistance through your body, something that can be altered by your water fluctuations. And your water, which will rise over the day anyway, can be dramatically adjusted by drinking, needing a wee, having a wee, water retention caused in varying amounts by varying foods, water retention in muscle after exercise... so yeah. They're rubbish. They're telling you your water level may have recently altered, which is of no real use.

Measuring tapes taken at various points (The Covert Bailey Formula, for example, where you take hips (arse), waist, wrist, calf and so on) can actually be more accurate but were invented for and are tailored to men's shapes. You can still use them to see month-on-month changes, but really, obsessing over the figure itself is only necessary for those preparing for bodybuilding competition.

Rufusgy · 14/09/2015 19:10

Ah thanks for the explanation. I've returned them to Amazon, just going to judge by the mirror from now on. The last reading was "healthy" so I'll take that.

OP posts:
beardsrock · 14/09/2015 20:06

I can't believe someone hasn't mentioned the mung bean fettuccine yet! Shock

OurBlanche · 15/09/2015 12:05

If you use fettucine a tape measure and accurate, normal scales, you can track muscle mass gain and fat loss indirectly.

You may not lose weight but might lose inches, therefore must have lost fat and/or gained muscle mass.

This is the only way to properly track weight changes. No fat calipers, no mad machinery, just scales and a tape measure. Anything else is hope over experience, or a damn good salesman.

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