Body Fat% is a way off PART3

yes, i'm afraid you are correct. there may be something in the impedance measurement but basically these scales just take your configuration inputs of gender, age, weight, height, activity class and give you body composition numbers based on population averages.

this allows garmin to claim "The body composition metrics provided by Index S2 compares to known gold standard methods (Dexa scan, Bod Pod, etc.) favorably on average" because literally, they are based on averages derived from such methods so "on average" they will compare well but for any given individal (especially someone outside the norm) they may not.

i'm sure garmin want to present some evidence that this is not a fair assessment but they are obviously unable to do so or they would have since they have supposedly done the testing to be able to make their carefully worded but misleading claim.

what would be really interesting if someone wants to donoate their body to science and do an experiment for us is to notably change your body composition, without changing your weight. go from being lean with muscle weight to losing your muscle weight but replacing it with fat. or the harder but more positive version, lose fat and build muscle to replace it. so none of the inputs to the scales have changed, other than th ebody composition as supposedly measured by impedance. with a sufficient lifestyle change you'll be clear what has changed in your body composition but will these scales be able to tell?

We already donated our money to this lost cause. So I reckon it should be a Garmin volunteer …

In the other closed threads I saw stuff about consenting to investigations, which I would volunteer for.  I also saw something about opening a ticket, how is that done?

Like many other people here my body fat measurements are significantly off.  I know body fat measurements are always messy (even DEXA) but I was expecting something better than BMI approximations which frankly is a less than useless (read harmful) tool.  The main reasons I bought this scale:

• to get a consistent heuristic that's within about +/- 5% of my three point jackson and pollock caliper measurements
• to input body fat to garmin connect since garmin connect will not let me do this manually
• to avoid the hassle of calipers

Given my amateurish calipers tell me I'm about 13% body fat, and given I can - albeit with good downlighting - see abdominal muscles there is no way I am 24% body fat.  Having a delta of ~10% does not inspire trust in the tool.

I would like to either volunteer for the investigation or open a ticket.  Please don't share the link to usage instructions or comment on impedance;  Instead please investigate and update your firmware.

AC has only to configurations. AC1-7 is one and AC8-10 is another. So it does not matter if 8 or 9 all are in AC8-10. 

I have the index scale 1 and I am getting this problem too. My body fat % percent dropped from 20% to 13% overnight.

I my case was the opposite. I used to be from 7% to 8% one year ago on my Index Scale 1. Now I am getting 20% to 22% on my new Index Scale 2. My weigh did not change at all. Even if I am less fit than before, does not look accurate. 

Try one thing. Change only your age and look at the results. If you %BF changes significantly, then you are in the same boat as most of us

Garmin-AmberD last update was three months ago. Any news?

My activity category was set to 8. I didn't change it, not sure what happened. I set it back to 6 and my % body fat returned to normal.

personally I just gave up.  I went through help desk and they didn't really understand the problem and asked to see measurements from other scales.  The issue isn't even about garmin vs other it's about the same garmin scale vs the same garmin scale.  My mass can change by half a pound and my body fat somehow swings a few percentage points.