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what's your body fat percentage?

PostPosted: Mon Jun 07, 2010 9:44 pm
by slodki
i just one of those scales that reads your body fat.
not the most accurate, but ya know.
16%

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 10:47 am
by baldy
Been down to 9% before in my running skinny emo phase. These days I am a lot more respectable, knocking on 20%, but still ripped.

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 11:33 am
by VeganGraham
How does a scale differentiate between fat and muscle ?
Doesn't it just make a guess based on weight and height ?

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 12:34 pm
by vegieburger
the scales have conductors that you put your feet on and they send an electrical current through your body (muscles conducts electricity better than fat) and it calculates your body fat percentage by how long it takes the current to get through your body (taking things like age, sex, height and weight into account) but they are not very accurate and things like how much water you have recently drunk can change the result.

I do not know my bfp and have no desire to find it out as I am sure it would be quite depressing.

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 12:47 pm
by VeganGraham
Oh, I see, I didn't realise they were that sophisticated.

So how would measuring the electrical resistance between the feet work on someone like me ? The current would go up and down my muscly legs and miss out my fat belly. :D

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 1:06 pm
by Linnéa76
I think you're right, BGW. There are devices where the current goes through the whole body (you hold the other pole with your hands). But if just the feet are in contact with it, only the lower body is measured and apparently the body fat percentage is underestimated for men and the other way around for women.

Re: what's your body fat percentage?

PostPosted: Tue Jun 08, 2010 11:32 pm
by vegieburger
I just assumed it could go all the way through your body from your feet. I carry most of my fat in my 'booty' and thighs, which might explain why ages and ages ago when I used on of these I got a much higher result than I expected. I think it also assumes that women do not have that much muscle so I'd hate to see the bfp a woman who was heavy because she had a lot of upper body strength would get.

I'm curious as to the most reliable, yet accessable, method of bfp calculation?

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 4:17 am
by slodki
usually people who work at a gym are trained in using calipers, if used over time and averaged this is accurate. the same kind of technology that makes a body fat scale work can be used in various places on the body and averaged. also the most accurate way of measuring body fat is a water tank test, but not very accessible. you can train yourself with the calipers and use that and calipers are not very expensive.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 5:12 am
by hardcore iv
[quote="vegieburger"]I just assumed it could go all the way through your body from your feet. I carry most of my fat in my 'booty' and thighs, which might explain why ages and ages ago when I used on of these I got a much higher result than I expected. I think it also assumes that women do not have that much muscle so I'd hate to see the bfp a woman who was heavy because she had a lot of upper body strength would get.


I think this could be remedied by doing a handstand on the scales :)

[quote="vegieburger"]I'm curious as to the most reliable, yet accessable, method of bfp calculation?


Aye, densitometry/hydrostatic weighing (you might have seen it on the simpsons episode when Homer goes to space:) ) was the best method to get BF% for a long time, but DEXA scans are now considered by many to be the most accurate and can give all kinds of other useful info about your body composition like bone density.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 5:30 am
by mabli
I was around 17% in March but Ive toned up more since then so probably less now, it was measured on a machine that I stood on and held onto with my hands, it calculated my height too.

Dont know if the machine is accurate, it just happend to be there so I had a go.

Why would someone want to know this info btw?

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 6:29 am
by vegieburger
[quote="hardcore iv"]I think this could be remedied by doing a handstand on the scales :)


lol, there is one of these at my uni gym, I think I should put a sign up explaining that to get a full body reading you need to do a handstand and then sit back and watch the fun begin. Thats if they ever get the thing repaired.

I wouldn't mind knowing my bfp, but I'm not keen enough to go to much effort to find out, although this is in large part because I am scared that the percentage would be too high. Ignorance is bliss after all.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 6:45 am
by hardcore iv
[quote="mabli"]

Why would someone want to know this info btw?


It is handy to know BF% if you are wanting to lose weight as most popular weight loss methods cause a a decrease in muscle mass rather than body fat. Once you know your BF% you can do a little mathematics and figure out how many kg of fat you would need to lose to get to a certain BF%. You would periodically get measured again to see if your loss in scale weight is due to fat or muscle loss.

For example, I got mine measured about a year ago with calipers and it was about 27% at a weight of about 105kg (105x0.27=28.35kg) So, if I wanted to get to 15% I would need to lose 12.6kg (28.35-(105x0.15)=12.6) of fat.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 10:58 am
by Alistar
16% is pretty low for a woman isn't it? I thought the average for women was about 25%?

I imagine I'd be around 12%. Quite glad I've put a bit of weight on recently as I was too light before. Feel a lot stronger because of it.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 1:29 pm
by mouche
I was 14% a year and a half ago, right before losing a few kilos and getting a lot leaner.

A few casual measurements with calipers about 6 months ago suggested a sub-10% body fat percentage, so I reckon I'm still hovering around or just below 10%.

Re: what's your body fat percentage?

PostPosted: Wed Jun 09, 2010 1:44 pm
by vegan hal
[quote="Alistar"]16% is pretty low for a woman isn't it? I thought the average for women was about 25%?

I imagine I'd be around 12%. Quite glad I've put a bit of weight on recently as I was too light before. Feel a lot stronger because of it.


i dunno. from your avatar (photo), you look a little more than 12%. :P

me, i have no clue my BF%. heck, i don't even know my weight. would like to find out both someday.