bio impedance analysis weighing scales accuracy

v638sg7k1a92bx

How accurate are these scales? I must say I’m a bit sceptical that invisible electric currents can detect heart rate, body fat, bone density ffs.

Is this real or fake?

leanin2019

Zyaire Obnoxious Tongue-lashing wrote: »

How accurate are these scales? I must say I’m a bit sceptical that invisible electric currents can detect heart rate, body fat, bone density ffs.

Is this real or fake?

At least 5 percent too generous in my case I'd say.

Although the trend is probably consistent.

Photos and videos in minimal clothing might be a better metric, along with weekly average scale weight unless your new to weight training and are building muscle while losing fat simultaneously.

That and a measuring tape or judging by how your clothes fit / don't fit

Macy0161

My Renpho one's matched a Dexa for me, in "Athlete" mode. But I would say consistency is what you want rather than necessarily the accurate.

I didn't get the dexa to test them (it was part of the UCD genofit study), and I really got the scales as I can sync them around various apps without manually updating. I weigh in --> scales to renpho app via bluetooth --> renpho to fitbit --> smartscalesync --> Garmin Connect/ myfitnesspal/ TrainerRoad.

leanin2019

Macy0161 wrote: »

My Renpho one's matched a Dexa for me, in "Athlete" mode. But I would say consistency is what you want rather than necessarily the accurate.

I didn't get the dexa to test them (it was part of the UCD genofit study), and I really got the scales as I can sync them around various apps without manually updating. I weigh in --> scales to renpho app via bluetooth --> renpho to fitbit --> smartscalesync --> Garmin Connect/ myfitnesspal/ TrainerRoad.

I have a garmin scales so goes directly to garmin connect. Was an expensive scales though didn't realise there was an indirect way to sync weight to garmin indirectly

v638sg7k1a92bx

How reliable is the science behind these. I can’t understand how standing on a scales can measure heart rate, bone density etc. Are they taking your weight, height and extrapolating based on that? Still wouldn’t explain heart rate.

Mellor

Zyaire Obnoxious Tongue-lashing wrote: »

How reliable is the science behind these. I can’t understand how standing on a scales can measure heart rate, bone density etc. Are they taking your weight, height and extrapolating based on that? Still wouldn’t explain heart rate.

The BF% is based on electrical resistance. It's highly variable due to hydration. I don't think weight are a bit factor, it's a %.


Similarly for heart rate. Why would height and weight be a factor?
Whether a scales can do it depends on the quality of the product. But I don't think there any issue with the concept of measuring heart rate electrically. How do you think it's done in hospitals.

Macy0161

Zyaire Obnoxious Tongue-lashing wrote: »

How reliable is the science behind these. I can’t understand how standing on a scales can measure heart rate, bone density etc. Are they taking your weight, height and extrapolating based on that? Still wouldn’t explain heart rate.

You enter your height in an app, and then any of the body composition measures are by Bioelectrical impedance.

They're estimates, but they seem to be reasonably accurate for the most part - given what I've seen on cycling forums where people have consistently tested them against Dexa which are readily available in the US. But most people use them for the trend rather than absolute, so it's about the user going at the same time/ same physical state as far as possible.

Mine doesn't do heart rate, but it's the same method as a chest strap, only through your feet!

bladespin

Miles off, went for a dexa scan and turned out the impedance scale was reading literally twice the scan result: 26 vs 13. Now I just half the value as it does seem to be consistent anyway.

v638sg7k1a92bx

Mellor wrote: »

The BF% is based on electrical resistance. It's highly variable due to hydration. I don't think weight are a bit factor, it's a %.


Similarly for heart rate. Why would height and weight be a factor?
Whether a scales can do it depends on the quality of the product. But I don't think there any issue with the concept of measuring heart rate electrically. How do you think it's done in hospitals.

But how does it read your heart rate and blood pressure from your feet? I’m just trying to understand how the scales can take all these readings just by standing on it?

In a hospital they usually use a monitor.

leanin2019

bladespin wrote: »

Miles off, went for a dexa scan and turned out the impedance scale was reading literally twice the scan result: 26 vs 13. Now I just half the value as it does seem to be consistent anyway.

What scales was that? I imagine it varies between models.

Mine is about 5% too generous and I have had a few dexas.

bladespin

leanin2019 wrote: »

What scales was that? I imagine it varies between models.

Mine is about 5% too generous and I have had a few dexas.

It's a salter, not very expensive etc, it's deadly accurate on weight though maybe I should stand on one foot.

Macy0161

bladespin wrote: »

Miles off, went for a dexa scan and turned out the impedance scale was reading literally twice the scan result: 26 vs 13. Now I just half the value as it does seem to be consistent anyway.

"Athlete" mode brought mine down to match the dexa. I wasn't considering myself an athlete, but I obviously do enough!

Mellor

Zyaire Obnoxious Tongue-lashing wrote: »

In a hospital they usually use a monitor.

A monitor reads your heart rate electrically.
So does one type of HRM. Newer types are optical.

Whether a cheap scales is accurate is up for debate. But the science makes sense. Detects electrical currents.

ILoveYourVibes

Even a dexa scan can be off by 10% and even more if the person operating doesn't know how to do it.

Even bone density tests by DR are not 100% accurate. So a dexa scan or a bio impedance scan by a lay person ...its anyone's guess.

Its not just the machine but how you operate it.

My dad went for two diff bone scans by Drs in the same week ..got differing results ...the dr made an estimate between the two.

Its a huge problem because people think they have made huge jumps in increasing bone density when its possible they haven't.

rubadub

ILoveYourVibes wrote: »

Its a huge problem because people think they have made huge jumps in increasing bone density when its possible they haven't.

And with fat measurements they think they have packed on loads of muscle. I remember reading outrageous claims by educogym done by fat measurements too. e.g. somebody would lose 2kg of weight, they would take BF% readings before and after and then have bizarre claims like you had lost 6kg of fat and put on 4kg of muscle.

Lots do this, as though your body is only comprised of fat & muscle, no accounting for water or glycogen or what is in your colon.

Alf Veedersane

rubadub wrote: »

I remember reading outrageous claims by educogym done by fat measurements too. e.g. somebody would lose 2kg of weight, they would take BF% readings before and after and then have bizarre claims like you had lost 6kg of fat and put on 4kg of muscle.

In 6-12 weeks.

rubadub

Alf Veedersane wrote: »

In 6-12 weeks.

The old ones were 12 days, here is an example from an old thread, it was €149 for 12 days there, so this was no typo mixing up days/weeks

Finns25 wrote: »

Just saying I did the 12 day program about 6 years ago. I lost 2.5stone in weight and put on 1.8stone in muscle. It takes about 20 min a season. Depends how quick you can complete the circuit. And it hurts like he'll. Like Arney says the pump is mad. Well worth it. Was money well spent for me.

11.43kg of muscle in 12 days.

Alf Veedersane

rubadub wrote: »

The old ones were 12 days, here is an example from an old thread, it was €149 for 12 days there, so this was no typo mixing up days/weeks



11.43kg of muscle in 12 days.

:D:D

I was going to say "you couldn't make it up" but, well, they obviously have.

Easier to sell putting on a nonsensical amount of muscle rather than "you lost a pound and a half in 12 days for €149"