Yet Another Cycling Forum

General Category => The Knowledge => Health & Fitness => Topic started by: ABlipInContinuity on 19 December, 2008, 11:33:52 am

Title: Min percentage body fat
Post by: ABlipInContinuity on 19 December, 2008, 11:33:52 am
Just wondering on what you peeps think is a safe minimum?

Wikipedia says, for athletes, it's 6-13%. I'm just on the lower end of that range now - and concious I'm not an athlete. However, Wikipedia says, for a man, that essential fats are about 2-5%, so that suggests I'm okay?

I recall my fitness instructor* in my younger days refusing to let me continue using the gym if my body fat dropped below 12% and telling me to go and eat more Pizza.

*she was seriously well qualified and well read up
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 11:38:48 am
I'd have to look this up, and my PhD thesis is not here right now, but I seem to recall that "body fat" as measured/defined clinically can exclude the very small % essential fat, which is in odd places like the bone marrow and nervous system.

So you'd need to check the definition used.
Title: Re: Min percentage body fat
Post by: andygates on 19 December, 2008, 12:08:56 pm
Under 5% as determined with calipers is heinously low and unhealthy.   Under 10% is very lean.
Title: Re: Min percentage body fat
Post by: clarion on 19 December, 2008, 12:09:56 pm
Not a problem I've ever had to face ;D
Title: Re: Min percentage body fat
Post by: Hello, I am Bruce on 19 December, 2008, 01:42:22 pm
How was your bodyfat measured?  It's very difficult to measure body fat when the percentage is very low.  I got measured by callipers, overall density (body pod) and DEXA.  Estimates varied from (I think) 5-8%.

I'm certain that I'm at the lower limit, but I don't have any health problems I eat lots and my weight is always steady.
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 01:53:44 pm
If you're at the limit, I'd not trust calipers at all.  They're used to measure subcutaneous fat, and you'll have almost none, so the regressions to calculate total body fat break down.   For us fatties, they're pretty good :)

DEXA on its own is good for bone density, but extrapolation to fat/fat-free mass is a bit iffy.

Total body immersion is about as good as it gets.  If they combined that with DEXA or with K40 or tritium dilution, then it would be a very good measurement of actual body composition
Title: Re: Min percentage body fat
Post by: inc on 19 December, 2008, 02:03:59 pm
Just wondering on what you peeps think is a safe minimum?

- and concious I'm not an athlete.


If you are <5% body fat, not an athlete,  eating normally and have been higher ( you mention 12%) something doesn't look quite right. I assume you have some concerns posting here and looking at Wikipedia.
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 02:08:51 pm
That was the reason for my question about how it was defined - also how it was measured.  6% is very low if you are not seriously training and are eating OK.  But if it's actually 11% then that'd be a bit more understandable.
Title: Re: Min percentage body fat
Post by: ABlipInContinuity on 19 December, 2008, 02:18:16 pm
It's an electronic widget bought from Lloyds pharmacy.

I'm not overly worried. It's gradually fallen from just over ten percent to now nine percent.

I probaby just need to eat a bit more. Explains a bit possibly why I've been tiring lately.
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 02:21:38 pm
It's an electronic widget bought from Lloyds pharmacy.


Oh OK.

It's totally crap then.  Whatever body fat it tells you, it'll be wrong.

There's a thread somewhere here on why. edit: here

Body composition monitor... (http://yacf.co.uk/forum/index.php?topic=6142.0)

I suspect you can get > 10% shift by drinking a bit more/less, or being a bit hotter/colder
Title: Re: Min percentage body fat
Post by: ABlipInContinuity on 19 December, 2008, 02:53:51 pm
OIC!

The reading, if anything, is quite consistent.

And it's quite complimentary about my amount of muscle and shows me to be 67% water.
Title: Re: Min percentage body fat
Post by: inc on 19 December, 2008, 03:42:48 pm


It's totally crap then.  Whatever body fat it tells you, it'll be wrong.

There's a thread somewhere here on why

Mal

Having now read that thread and see you are the resident expert, do the Tanita scales come into the same crap category, or are they useful for measuring trends.
Title: Re: Min percentage body fat
Post by: vorsprung on 19 December, 2008, 03:47:42 pm
I don't think of myself as an "athlete" but on the resting heart rate BPM table apparently I am

I don't think I'm likely to get to your level of body fat % but don't let the athlete label bother you

Eating pizza sounds like a good idea
Title: Re: Min percentage body fat
Post by: hellymedic on 19 December, 2008, 03:53:41 pm
Does maffie complain that you look/feel like someone straight out of Belsen?
A figure of <9% would give that appearance.
Otherwise, I might not believe the machine...
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 04:11:43 pm


It's totally crap then.  Whatever body fat it tells you, it'll be wrong.

There's a thread somewhere here on why

Mal

Having now read that thread and see you are the resident expert, do the Tanita scales come into the same crap category, or are they useful for measuring trends.

Same crap category.

They may be some use in measuring trends, but all they'll actually measure is how muscular your knees and ankles are, and how well hydrated you are.  You'll be getting no real information about body fat.  Physics says no ;)
Title: Re: Min percentage body fat
Post by: border-rider on 19 December, 2008, 04:12:32 pm
Does maffie complain that you look/feel like someone straight out of Belsen?
A figure of <9% would give that appearance.
Otherwise, I might not believe the machine...

Hellymedic as ever speaks good sense.  Your own eyes are a better indicator of body fat than one of these machines.
Title: Re: Min percentage body fat
Post by: fred the great on 19 December, 2008, 04:48:46 pm
Ah, Mr Expert I love my Tanita scales even if thay are allegedly crap. For weight measurement they appear to be more accurate than my Hospital Digital Scales - I checked this two weeks ago and the nurse then brought another scale that proved the main ones were inaccurate by more than 2 Kg. As to fat percentages they also seem to be a pretty good guide.

This is based upon my own health experience over  more than 5 years whereby my weight and presumably fat can vary by as much as 30%. Yes really,  the details are concerned with one kidney not working properly. The Tanita scales have always produced  sensible figures. Perhaps the % fat in the legs is representative of the general body fat? I recall a similar discussion a few years ago :P

Anyway, I just don't need anything more accurate and still use them regularly :D
Title: Re: Min percentage body fat
Post by: border-rider on 20 December, 2008, 12:09:10 am
Yes really,  the details are concerned with one kidney not working properly.

It's more likely picking up an electrolyte imbalance then.

Quote
Perhaps the % fat in the legs is representative of the general body fat? ]

Possibly, but that's not what it's measuring.  It doesn't measure fat directly, it measure conduction pathway. Conduction pathway is determined almost entirely by the smallest conducting cross sections - which is your knees and ankles.  It's effectively measuring the conducting cross section of those  bits of you (only), which is not dependent on the amount of fat.

The fallacy in its conception is that it is in some way a whole-body measurement.
Title: Re: Min percentage body fat
Post by: fred the great on 20 December, 2008, 02:11:38 am
Correction. I know what the machine is doing, I just explained my thoughts poorly.

Title: Re: Min percentage body fat
Post by: Marmitegeoff on 20 December, 2008, 12:07:25 pm
Ah, Mr Expert I love my Tanita scales even if thay are allegedly crap. For weight measurement they appear to be more accurate

I to like the Tanita scales.  for the weight measurement ( I do not need scales to know the fat %age of this lump of La*d )   ;D

But the scales are very accurate,  The same weight no matter how many times you step on them.  Also Weigh then drink a pint of water or so and weight goes up by .4kg.   That is impressive accuracy at the price.

Geoff
Title: Re: Min percentage body fat
Post by: JonBuoy on 20 December, 2008, 12:25:14 pm
Repeatability and accuracy are not the same thing.
Title: Re: Min percentage body fat
Post by: hellymedic on 20 December, 2008, 12:46:48 pm
Ah, Mr Expert I love my Tanita scales even if thay are allegedly crap. For weight measurement they appear to be more accurate

I to like the Tanita scales.  for the weight measurement ( I do not need scales to know the fat %age of this lump of La*d )   ;D

But the scales are very accurate,  The same weight no matter how many times you step on them.  Also Weigh then drink a pint of water or so and weight goes up by .4kg.   That is impressive accuracy at the price.

Geoff

<pedant>
Given that a pint of water weighs .568 kg, I would not be impressed with scales that registered a 0.4kg gain after drinking a pint.
Do you serve short measures?  ;) ;D
<pedant>
Title: Re: Min percentage body fat
Post by: Maffie on 21 December, 2008, 09:06:09 am
Does maffie complain that you look/feel like someone straight out of Belsen?
A figure of <9% would give that appearance.
Otherwise, I might not believe the machine...

I have said over the last few weeks he's getting slimmer, he does eat alot  :demon: but have noticed him shrinking
Title: Re: Min percentage body fat
Post by: hellymedic on 21 December, 2008, 10:51:28 am
Blip shouldn't be shrinking if he's exercising normally (whatevever that is) and eating enough. It's Christmas; I hope you all enjoy seasonal fare!
Seriously, if he's shrinking despite adequate food intake, it might be worth investigating, eg doing thyroid tests.
Title: Re: Min percentage body fat
Post by: Charlotte on 21 December, 2008, 11:13:42 am
Daniel - if you post a picture of yourself naked, we can all give you our opinion  :)
Title: Re: Min percentage body fat
Post by: Hot Flatus on 21 December, 2008, 11:21:46 am
Please don't.
Title: Re: Min percentage body fat
Post by: Marmitegeoff on 21 December, 2008, 11:58:00 am

<pedant>
Given that a pint of water weighs .568 kg, I would not be impressed with scales that registered a 0.4kg gain after drinking a pint.
Do you serve short measures?  ;) ;D
<pedant>

Probably not a full glass and the measuring is in steps of 0.2kg so enough room for error there  ;)

Repeatability and accuracy are not the same thing.
 
Accepted 

But awhile ago I bought the same scales as my Dr had and they could vary by several lbs (yes it was a while ago), each time I stood on them,  Solid floor etc. taken care of.

and they were more than twice the price of the Tania ones.   :(

But to track changes in weight I feel that the Tania ones are good value for money.

This lump of La*d is going to try not to get to much bigger over the festive period.

Ride more  eat less
ride more  eat less

Etc

Geoff
Title: Re: Min percentage body fat
Post by: Jezza on 21 December, 2008, 08:44:27 pm
Judging by your last few posts (anxiety about performance review, repeated threats from motorist, stress of local chav interactions, as well as other issues you've mentioned,) you're probably worrying yourself away.

I prescribe quantities of pasta at regular intervals to redress the physical aspects, and practicing meditation to take care of the mental.   
Title: Re: Min percentage body fat
Post by: Chris S on 21 December, 2008, 09:38:03 pm
I have a set of Tanita scales. I'm considering performing an experiment. I'm going to attempt to drop 10Kg of lard come the New Year, in time for (perhaps) the Kidderminster Killer Audax (or similar).

I'll take a weekly BF/Weight measurement off the Tanita, amongst other measurements, throughout the spring, to see how it shapes up as I shape up  :thumbsup:.
Title: Re: Min percentage body fat
Post by: simonp on 22 December, 2008, 09:27:24 pm

Mine have shown between 15.5% and 19%.  The 19% is probably what I'd get Right Now.  The 15.5% is when I peaked around the time of the BCM in May.

I think it does track reasonably well when I can tell I've lost fat due to my physical appearance, pinchability etc.

I thought I'd go check.  I'm now being told 20%.  Damn thing doesn't work after all.  ;D
Title: Re: Min percentage body fat
Post by: Blodwyn Pig on 24 December, 2008, 05:52:16 pm
SO!   50% is too much then, wat are YOU saying!!!!!!????????? Im FAT!!!!!!!!
Title: Re: Min percentage body fat
Post by: fred the great on 25 December, 2008, 09:31:40 am
I don't know but your Avatar is the same as a lady that we knew at t'other place?

Is it you?

Sorry OT but nice to meet old friends, wot? ;)
Title: Re: Min percentage body fat
Post by: Velvet on 25 December, 2008, 12:43:34 pm
Nope, just the same as my old avatar at t'other place :)  Well, nearly the same.  I decided on a different one for here, when I was between-places, as it were :D

Merry Christmas and all that, tho!
Title: Re: Min percentage body fat
Post by: Bledlow on 25 December, 2008, 04:22:14 pm
My scales claimed last night that I was 15% fat, which is slightly down on a month ago. I ought to get a proper measurement done, to give some idea of their (in)accuracy.

172 cm, 67 kg, BMI 22.6. At my hill-climbing peak, I was 58 kg/BMI 19.6, & although I didn't know my body fat percentage, I strongly suspect it was in single figures. I don't desperately want to be back there, but it'd be nice to lose the bit of flab I now have round my waist.