Hi all- my first post so please forgive any faux pas. I’ve recently bought the Scale X and am finding the muscle mass reading waaayyyy off. I’m a chubby middle aged woman with very little muscle definition or strength but my results consistently come back in the high 50’s percent-wise, or above optimal. I’ve tried all the suggested fixes (clean feet etc) without effect. I know the most important thing is trend, but I’d like to at least see a result that reflects my general condition. Can hardly aim for greater muscle mass when it’s already so high? Or am I missing something obvious? TIA
I am a chubby out of shape elderly (Ha!) male. My Wyze scale is older and doesn’t do percentage of muscle mass.
My weight right now is 215lb and my muscle mass is calculated as 135lb so doing the math, my muscle mass is 62% which is WAY off.
I wouldn’t take these calculations seriously.
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Welcome to the forum @amryan
Most smart scales use a method called bioelectrical impedance analysis (BIA) to estimate body composition, including muscle mass percentage. One of the limitations with it is that it only sends electrical signals through your feet, so it is mostly measuring the resistance through your legs and across your pelvis, but not really through the top half of your body.
I have long been telling Wyze they should make a scale that has a handbar too so the BIA will go through the top half of the body as well.
Having said that, most research has found that BIA estimates usually have a Standard Error of Estimate that is typically within 2.6% - 4% of the accurate DXA measurements for body fat percentages. So it’s rarely too far off from the real amount. So it is generally a reasonable approximation.
Granted there are things that can affect BIA accuracy such as hydration levels (dehydration overestimates body fat), recent food and drink intake, physical activity, and sometimes device calibration.
So I won’t guarantee the scale is within average S.E.E. measurements since I don’t work for Wyze, but in general, it’s unlikely to be extremely far off from what you’d get with a more accurate DXA measurement. That would be the only way to know…go get a DXA measurement and before changing anything else with your body (no eating drinking, etc), measure on the scale again and see how much of a difference there is. I would guess it’s under 5% different.
Regardless, as you said, even if it is inaccurate, as long as the trend is consistent that helps you know whether you are going up or down over time.
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Thanks both for your insights. Still unconvinced and disappointed that one of the key features I was seeking is not really of use, but very interesting to learn more from you 
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Are you sure the scale uses BIA? I’m starting to think it uses only your weight, height, and age to estimate body composition. I’ve been logging data for a while and I’ve noticed that when I get a certain weight reading all the other numbers are the same.
Absolutely sure. You can even test it. Step on it with shoes or something else that won’t allow the electrical signal to go through you. It will only record your weight.
Also, if your feet get too calloused it will fail.
There are other more advanced ways to test if it changes (such as your body water percentage changing. when you first wake up (ie: long period of not drinking) drink a ton of water, weigh yourself right away, then wait at least 30 minutes (the longer the better) without eating or drinking anything else after that weigh-in so you haven’t gained any weight since that control measurement and now after 30+ minutes weigh yourself again and see the estimate seem to change since you should a different impedance from increased body water (not just in your stomach). Your weight should be the same but the impedance will be different.
You can do the same thing just before you do some strenuous exercise and then again afterward. You might see changes in body water percentage, muscle mass, and body fat percentage due to fluid loss, but it couldn’t tell those things based solely on your age/H/W.
Also, if the batteries get low, it will stop doing the BIA and only do weight because there isn’t sufficient voltage for the BIA to work.
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We should make a bluetooth handbar that integrates with the scale.
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Definitely! I’ve been asking for this since the scale x launched. Having both the feet and handbar together are more accurate since The feet primarily measure the lower body and the handbar primarily measures the upper body, both together is a way more accurate picture. It’s not really a critical thing, but it would be kind of cool to have as an option.
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We almost made a smart jump rope at one point… don’t tell anyone
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I’ve definitely noticed this with Scale S.
How would that work if it’s not physically connected to the scale? I would expect a handlebar to need a physical electrical connection to the base in order to complete the circuit, at least if it’s going to provide more accurate results as I understand them.
Good point. Thinking about this, I think it partially depends on the intent. If you want the circuit to be completed from the arms to the feet, then yes, it would need to be wired. If you want it to just measure from arm to arm (Upper body only) and leg to leg (lower body only), separately, then I suppose Bluetooth would work.
Regardless, I’m okay with it being wired. I have just long wanted a hand bar option. 
Yeah, I was thinking about the way something like the Withings Body Scan apparently does it, with a tethered handle to provide more accurate measurements.
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