Which BF% test should I trust?

[Beautifulfreak]

I've got two sets of body composition scales, two different makes - Tanita and Homedics. They both give me a reading of 21%.

I work in a gym, and have a hand held bio electrical impedance monitor which gives me a reading of 25%!! The gym I belong to also has an identical set, and that one gave me a reading of 28%.

I had my personal trainer do me with calipers, BUT I was wearing a pair of bodycontrol tights/nylons at the time (dont ask, lol!!) and he gave me a score of 11%.

During my fitness assessment at the gym I go to today they did a test where I lay on the floor and had four sticky pads stuck to my hands and feet and had them attatched to a monitor via some wires: and THAT gave me 11% also!!

I know the calipers are the most accurate, but when I was told 11% I put that down to the innaccuracy caused by my attire that day. But to have that score repeated using the wired up test....I dont know now?

I am 5 ft 3 and 110-112lbs...I would have said a higher than usual BF% due to years of excessive dieting, but who knows?

Sorry for rambling I'm just confused and would appreciate any advice you may have on this...I'd like to be able to measure my muscle gains.

[The_Contrarian]

You look 11%...if that helps.

[matsimitso]

by ur pics id say round the 20% mark..
no way ur 11% like above said..

20% is not bad atal for a girl tho..

[BMMack]

Wouldn't the 'sticky pad' test just be another electrical impedence test? It may be more accurate than the scale version, but it seems like it's the same thing, and may have the same flaws. I'd see what the calipers say without the bodycontrol attire on. But the 20+ numbers seem too high and 11 seems too low, looking at you.

[matsimitso]

20 is not that high for a girl bro..
a girl at 14% bf would be Lean and prob have decent abs..

20-28(MAX) looks right.. coz u havnt got alot of muscle under there

[PennState]

I agree, somewhere around 20%. If you REALLY want to know you can get a water displacement test done. But do you really want to pay a ton of money just so you know for sure? My $35.00 mirror has done the trick for me for the past 3 years.

[greyhair]

In your avi, you look pretty light, but I don't think you look like 11%. Not enough muscle.
OTOH, 20% does not look right either, unless your holding a lot of internal fat.

All BF percentage calculations are estimations that have underlying assumptions that can be very wrong for individuals. For example, skinfold measurements only measure subcutaneous fat, internal fat stores are assumed to be some ratio between internal and subcutaneous fat. Additionally, there are underlying assumptions about contributions by bones, internal organs and muscle. All which can be very wrong for an individual.
However, if you are willing to forget the actual BF% and concentrate on changes in total caliper measurements (skinfold measurements) you can get a good idea of how your doing as far as overall fat loss is concerned. It is generally accepted that fat is lost fairly uniformly across the body and sampling subcutaneous fat loss will be a good indication of overall fat loss.

OTOH the electrical measurement is complete Cr*p IMHO. It measures electrical resistance which is dependent on water mass in the body. The more water, the less resistance. Fat has high electrical resistance, so more fat >> more resistance, more muscle >> less resistance. But more water retention in the vascular system >> less resistance too. Additionally bone is high resistance. Basically, the estimate is useless because of all the assumptions made. The changes are not even consistent for a person so you cant even determine if your making real progress, even if you ignore the absolute number it spits out.

Net-Net: use the skin calipers as a guide of progress, not as an absolute value.