Hi! Nice site. Here about discussion stumbled on BIA scales

[KerryJames]

Hi nice site and welcome.

Was a rower in my youth and for too long until 36.

Did a lot of Gym including heavyweights all those years but can hardly get myself into a gym today prefering the great outdoors. Am contemplating getting free-weights for home to get back some upper-body strength.

I'm an Exercise Physiology & Nutrition specialist (Sport Scientist) graduate of Otago University School of Physical Education and qualified High School Biology, Junior Science, and PE Teacher.

Have professionally practised since 1985, nearly 27 years, and practised as a weight-loss specialist.

Have come onto this site due to a thread I stumbled across that discussed "body fat percent" measuring and some erroneous comments being made somewhat repeatedly.

Perhaps I will leave it here with a view to gauging interest in my resuming at the discussion thread in question, and to leave with the accompanying attachment as a first morsel of food for thought! ...and that before 1997 I did my own process of validating (rather than relying on personal unsubstantiated unscientific opinions) the first being to test Taine Randell side by side with the DXA machine at Dunedin Hospital with results that were astounding!

Regards

KJGhuman body comp11098.DOC

[DANIEL8]

hi

why didnt you just click the "advertise with us!" button alongside the thread?

welcome anyway!

[KerryJames]

Hi Daniel,

sorry if I did not make myself clear. I am not wanting to advertise, I am wanting to discuss a topic, putting some factual qualification to it, and thought it fair enough to establish credentials first.

Regards and thanks for your welcome

KJGa

[thatwaslight]

Strong troll thread

[KerryJames]

?

[hhhh1]

can you just say in like a couple of sentences or so what your document says? after reading your autobiography I cant be fucked reading the attachment as well

[muscle99]

Strong troll thread

h i t t h e n a i l o n t h e h e a d

[KerryJames]

okay in a nutshell, it's calipers that are crap, BIA is validated against DXA, like all tools you gotta use them properly and understand them, even a blood pressure monitor gives a different value every minute, common sense and good judgement are required

how's that?

i'll simplify my intro since not appreciated

[DANIEL8]

okay in a nutshell, it's calipers that are crap, BIA is validated against DXA, like all tools you gotta use them properly and understand them, even a blood pressure monitor gives a different value every minute, common sense and good judgement are required

how's that?

i'll simplify my intro since not appreciated

we appreciate it, we just dont like reading novels this time of night

[Riccardo]

Ok

[trainlikeafreak]

how the f*ck are calllipars crap? :doh:

[hhhh1]

okay in a nutshell, it's calipers that are crap, BIA is validated against DXA, like all tools you gotta use them properly and understand them, even a blood pressure monitor gives a different value every minute, common sense and good judgement are required

how's that?

i'll simplify my intro since not appreciated

thanks

[thatwaslight]

Ok

Ok.

[trainlikeafreak]

Ok

Ok.

lol

[Pseudonym]

Come on guys, let's play nicely with the new person. I appreciate you all defending the site against people wanting to score free advertising (seriously - I do appreciate it) but he was trying NOT to spam us. Let's give him the benefit of the doubt until he proves otherwise.

Kerry, welcome to NZBB. I'm curious... are you saying that a BIA scale (like the Tanita scales) that can be affected by drinking a glass of water is more accurate than a DEXA test?

[pyro]

Your article claims that calipers are a poor measurement for accuracy, but you also stated that was only for a single site abdominal measurement, nothing about multiple sites which is regular practice for an experienced person. Obviously a 1 site caliper measurement isn't going to be accurate, I don't see your point at all. Did I miss something?

[KerryJames]

Hi Pyro,

the article assertions are not mine, it is a review, being 90% quoted from the review text by Roche, Steven and Heymsfield, experts in this field.

The paragraph dismissing calipers states "on one site alone" error is 8%. This sentence infers that when you add more sites you add more error into the final assessment.

The crucial thing in that paragraph was Lukaski's comment that a subcutaneous (skin-layer) fat assessment does not equate to a measure of fat in the rest of the body (visceral organs etc) and therefore cannot be used to state a "total body fat" value accurately.

From a body-building perspective I might use them simply for what they do since to get definition you don't want subcutaneous fat. That is, measure mm's of skinfold fat, chart results, and compare weeks and days of your peaking up (do you call it that in B-B'g?) at the same stage year on year. But, forget about using them to convert mm's to some idea of % "total body fat".

Regards

kjg

[KerryJames]

Kerry, welcome to NZBB. I'm curious... are you saying that a BIA scale (like the Tanita scales) that can be affected by drinking a glass of water is more accurate than a DEXA test?

Hi Pseudonym, thanks for the welcome!

BIA can't be more accurate than DXA since the "analysis" part of the BI"A" method is designed using DXA.

Take 10,000 people, measure with DXA then tweak your BIA cpu (computer chip!) to match those results.

If you drink a glass of water before a DXA test your body composition (BC) will change also.

We are looking at the whole body and components (proportions) of it.

If you drink a litre of water this is 1 kg. If you were 100kg 5 minutes before you are now 101kg. Do you then slam and throw out an ordinary weight-only scale for being inaccurate since it weighs 1kg one minute to the next?

Another scenario: A 100kg person loses 8kg of sweat in a 4 hr cardio workout. His total BF% was 30%. His weight is now 92kg. What has happened to his BF%? Do you expect his BF% on a BIA monitor to still say 30%?

100kg x 30%BF = 30kg Fat

Dehydrated weight, 92kg >>> 30kg Fat/92kg = 33% (32.6) FAT.

Total bodyfat % has increased near 3%!

Why is a Machine showing such responsive changes wrong?

That is, you dehydrate, or overhydrate, your proportions (components) of your total weight will naturally change.

This variation in the BIA method then stands to reason.

This is why body WATER % mesaurement is a key measure paired with body FAT measuring since one effects the other.

Monitoring hydration is the key to understanding your body composition values and a key in most sports for optimising performance.

If you BIA test in the morning cf late afternoon you will get slight variation in results also since bodyfluids shift dramatically periperal to central and back again through night and day. Trials have shown that BIA values are most accurate around 6pm before dinner, in a state of normal hydration (not thirsty, clear urine, not having just drunk a lot of water!), and not having just worked out. The cpu (analysis part) has been tweaked to compliance with these conditions ...this is how you get accuracy and reliability (consistency) ...this is refered to as "standardising of procedure" which is a key and crucial part of all scientific experimentation required in the use of all medical or scientific testing, from use of a thermometer, to BP monitor or DXA machine, to get "safe" results all testing "instruments" need to be used properly, as specified by instructions provided.

There is a fair bit of other stuff ...but later.

regards

kjg

[PeterDolan]

Why even use any type of composition test. It doesn't make you any more muscular or any more shredded. 6% BF on one person can look like 10% on another depending on how the distribute it. At the end of the day you either look lean or you look fat, scales or calipers wont change that

[mike27]

who does a 4hr cardio session?? :shock: and looses 8kg

[Riccardo]

Agree with Pete, what you look like in the mirror is what really counts. Like Kerry said the fundamental assumption that calipers make about subcutaneous fat being 50% or whatever is flawed because as you reach lower percentages of body fat the subcutaneous fat layer gets smaller and smaller proportionally to visceral fat. Therefore Calipers tend to underestimate lean individuals.

All this gets more complicated when you throw AAS into the mix which also effects fat deposition. The Mirror is the best measure of body fat.

[KerryJames]

who does a 4hr cardio session??

biking half the rail-trail into 35C head-wind can do it!

:shock:

[pyro]

who does a 4hr cardio session?? :shock: and looses 8kg

Certainly never lost 8kgs......But used to cycle a lot and a few races were over the 4hour mark.

[KerryJames]

crikey!

Certainly never lost 8kgs......But used to cycle a lot and a few races were over the 4hour mark.

it was an extreme example for illustrative purposes of basic body composition calculations.

a female would probably never have the total (lean) bodyweight that could allow an 8kg loss in body-water and not be hospitalised, comatose

a 110kg rugby player could lose 7% of their total bodyweight (8kg) from

extreme exertion ...seriously stressed.

;-)

[KerryJames]

Why even use any type of composition test. It doesn't make you any more muscular or any more shredded. 6% BF on one person can look like 10% on another depending on how the distribute it. At the end of the day you either look lean or you look fat, scales or calipers wont change that

The problem just using "the eye-ball method" is the degree of subjectivity, and the propensity of human beings to kid themselves, along with the subjectivity of deciding who wins by the decision of judges.

For example, say one year you won a title, you knew what you looked like in the mirror, and the next year you were absolutely sure you looked exactly the same in the mirror but you came 3rd. Was the competition better, were you worse shape (not according to mirror!), were the judges against you? What is the answer? Well, if I had spent a million hours training year after year I would want to put in as much objective measurement as possible to be sure "by the numbers" that I am in at least the same or better shape than before ...at least then I could know that if I definitely was in better shape, it was either better competition or crap judges, and I definitely did my PB!