In the industry we are in, and with such a focus on 'being lean', it is no surprise that everyone is curious as to what their BF is. However - in the female community on a whole, there is a gross distortion of what a persons BF usually is! So - on the request of a few members, I have put together this sticky to help.
Basic Definitions and Concepts in Body Composition
Body composition refers to the make up of lean tissue and fat tissue in the body. So:
- Lean Tissue - Composed of muscle, bone, organs, glycogen, blood volume, water, hair, nerves and a few other bits and pieces.
- Fat Tissue - Composed of different categories: essential fat, and storage fat.
- Essential fat - Required for life and physiological functioning. This is fat stored/ that is part of nerves, bone marrow, the organs (heart, lungs, liver, spleen, kidneys, intestines) and also the muscles. There is thought to be ~ 8-12 % in females and ~ 3-5% in males. The extra 'fat' that is essential for females is thought to be due to our requirement for babies and hormones. It is essential RESERVE fat found in breast tissue, genital regions and *gasp* lower body stores.
- Storage Fat - The 'cheese' factor. Generally divided into - VISCERAL fat (around organs and in the abdomen) and SUBCUTANEOUS fat (under the skin). In females, this is usually about 15% and males it is about 12%.
Measuring Body Fat %
There are many, many ways to find out your body fat percentage, and these all vary in accuracy and availability. Generally speaking - the more accurate the method, the more expensive and 'unobtainable' it is. Going from MOST accurate to LEAST accurate:
- DEXA scan – This involves a full body x-ray like that used for bone density scans. It is very accurate (although there WILL be a variation between machines - so best to get it done on the same machine by the same technician). There IS also a radiation factor (something to consider if getting multiple scans).
- Underwater/ Hydrostatic Weighing (also called water displacement) – An individual is submerged and weighed under water, with all the air blown out of their lungs and a percentage of fat and fat-free weight is calculated from body density. Very accurate when done professionally but not widely available.
- The Bod Pod - Similar concept to underwater weight, but the individual is placed into a small chamber and the amount of air displaced is measured by sensors and calculated into a BF %. Also accurate, but not widely available.
- Skin-fold measurements/ calipers – Folds of skin are measured with a caliper (pinching tool). The measurements are used in equations that link the thickness of skinfolds to percent body fat calculations. It can be done via '3 sites', '4 sites' and '7 sites'. The more measurements made, the more accurate the estimate. It is simple and available, but needs to be done by someone who is trained and there are wide variations in accuracy.
- Bioelectrical Impedance (BIA) – These are scales or hand-held devises that run an electrical current through the body to determine water content. They vary in accuracy according to the specific device (some brands are better than others), the number of attachment points (foot and hand electrodes are more accurate than hand held or scale devises), and the user. Example: if you use a SCALE only - the electrical impulse takes the path of least resistance - so travels up one leg, and straight down the other. Thus, it basically measures LOWER body %. If you use a hand held device, it only measures UPPER body %. Similarly - As they are based on WATER content - fluctuations in hormones/ hydration throw values out. So - the best results are obtained first thing in the morning after emptying bladder/ bowels, with no alcohol consumed for 2 days prior, and no exercise the night before, and - hormone free.
- Tape measure method - There are a number of formula based on several body measurements taken with a tape measure. It can be roughly accurate, but it does depend upon your ability to accurately measure as well as body shape/ type. Although LEAST accurate - it is especially useful for tracking yourself over time as it is readily available.
Body fat % in females
Generally speaking - most athletes range between 12-14% and 20%. Most fit females in the general community are 18-24%. Most every day females, well, usually above 24%. It is also important to note that a female who LOOKS thin does not necessarily mean she has a low body fat. This is the concept of 'skinny fat'. In females, the lowest values for body fat correspond to the essential fat content (about 8-12%). This level of fatness is extremely low (professional bodybuilder on stage low). And once a female reaches 12%, especially for prolonged periods, they will run into issues with health (lack of periods, decreased immune function, decreased recovery, decreased bone mass, etc).
Body Fat Categories for Women:
8-12% - Essential Fat
13-20% - Athletic Fat Levels
21-24% - Fitness Fat Levels
25-31% - Acceptable Fat Levels
>32% - Obese
Visual Estimates and why is it so inaccurate?
There are many reasons - firstly, people look different at different at the SAME body fat depending on where they hold their fat, and how much lean mass they have. Additionally, people make the mistake of comparing visual estimates in females and males - and, as discussed above, this is NOT correct... Essentially, you need to add on another 5-8% to a MALE estimate for an accurate guess for a female visual %. For example: a male 10% is roughly a female 15-17%. A male 3-5% is a female 8-12%.
It is also important to note that you need to look at the WHOLE person! So - in females, where UPPER BODY might be lean (eg: 10-12%), LOWER body may well still hold a LOT of fat (female stubborn fat) which will INCREASE their average bodyfat %.
Generally speaking - visual cues to look for in females:
- Upper back definition and shoulder/ delts usually come in first in females [mid to high teens]
- Abs separation and pec separation follows this [usually low to mid teens]
- Quad definition/ ham definition and Glute striations [single digit to low teens]
But NOTE: this is 'most' females (who have typical pear-body fat distribution) if an individual holds more fat in a MALE distribution (apple) then the cues will be different.
Some visuals to help:
^
The first is ~ 17% by DEXA scan. The second about 14% by DEXA.
If you have some pics as well as DEXA/ BODYPOD measurements of BF% - you could also post them in this thread to help people with accurately assessing their OWN bodyfat%.
Some Web Resources to Help?
PP presentation on Body Composition
Leigh Peele - How to Calculate BF%
Wiki on Bodyfat
Body-Tracker (online bodyfat % estimate)
|
-
04-11-2010, 03:17 PM #1
Body Fat % - What is it, and how to measure it!
Last edited by Emma-Leigh; 04-28-2010 at 01:53 PM.
-
04-11-2010, 04:32 PM #2
- Join Date: Jun 2003
- Location: Sydney, Australia
- Age: 42
- Posts: 12,481
- Rep Power: 5052
Fantastic post Emma.
I just wanted to add on that women have a tendency to underestimate their bodyfat percentage. I had a DEXA scan done a few years ago and at that time, I was fairly lean, with visible abdominal muscle, lats and rear deltoids. I estimated my body fat at approx 17-18% and was quite upset when my DEXA results showed 23%. My abdominal region was only 16% but my chunky lower body brought the average down...September 2006 - 9km Sydney Harbour Bridge Run - 45:25
August 2007 - 14km City to Surf - 77:00
September 2007 - Sydney Running Festival Half Marathon - Withdrawn due to stress fractures :(
September 2008 - Sydney Running Festival Half Marathon - 1:59.22
May 2009 - Sydney Morning Herald Half Marathon - 1:53:22
-
04-11-2010, 06:08 PM #3
-
04-11-2010, 09:20 PM #4
-
-
04-11-2010, 09:40 PM #5
^
Oh - good idea! For those in Sydney - Australia, I would check out Body Composition Australia. Jarrod is an exercise physiologist located in the center of sydney. He does DEXA scans at very reasonable prices and you can compare serial scans over time to monitor progress. He is also lovely (say hi for me if you go)!
-
04-11-2010, 10:15 PM #6
-
04-11-2010, 11:07 PM #7
-
04-12-2010, 03:07 AM #8
-
-
04-12-2010, 08:59 AM #9
Wow great post, that woman at 17% I would have guessed lower too, she looks so awesome, but how is it you can see her quad deffinition there but your description says that should be low teens..
Also are those descriptions talking about someone with muscles flexed or unflexed? Because Abs can look a lot different on a flexed and relaxed stomach. Same with quads.."The word aerobics came about when the gym instructors got together and said, "If we're going to charge $10 an hour, we can't call it jumping up and down." ~Rita Rudner
-
04-12-2010, 12:44 PM #10
-
04-19-2010, 04:46 PM #11
-
04-21-2010, 09:23 PM #12
-
-
04-23-2010, 04:27 PM #13
-
04-28-2010, 10:23 AM #14
-
05-10-2010, 07:54 PM #15
-
05-11-2010, 12:08 PM #16
- Join Date: Jun 2003
- Location: Sydney, Australia
- Age: 42
- Posts: 12,481
- Rep Power: 5052
September 2006 - 9km Sydney Harbour Bridge Run - 45:25
August 2007 - 14km City to Surf - 77:00
September 2007 - Sydney Running Festival Half Marathon - Withdrawn due to stress fractures :(
September 2008 - Sydney Running Festival Half Marathon - 1:59.22
May 2009 - Sydney Morning Herald Half Marathon - 1:53:22
-
-
05-21-2010, 10:22 AM #17
-
05-21-2010, 01:52 PM #18
-
06-01-2010, 03:18 AM #19
Just a touch more info for all -> the impact of blood flow and temperature on BIA readings:
Skin temperature and skin blood flow affect bioelectric impedance study of female fat-free mass.
LIANG, MICHAEL T. C.; SU, HUEY-FEN; LEE, NING-YUEAN
Medicine & Science in Sports & Exercise. 32(1):221, January 2000.
[Article.]
AN: 00005768-200001000-00033.
AB LIANG, M. T. C., H.-F. SU, and N.-Y. LEE.
Purpose: This study examined the effects of skin temperature (Ts) and skin blood flow (SKBF) on bioelectrical impedance (BIA) measurements of body composition in healthy young females.
Methods: The Lukaski (FFMLUK) and Guo (FFMGUO) BIA equations for measuring female fat-free mass (FFM) were used. All subjects (N = 20, age = 18-22 yr) underwent the following measurements under three ******t temperatures (Tamb): Ts and SKBF for the calf, thigh, biceps, and chest; oral temperature (TOR); and the BIA measures of resistance (R) and reactance (Xc). The three Tamb were 17, 25, and 35[degrees]C which were considered as cold (CT), neutral (NT), and hot (HT) conditions, respectively. Their underwater weighing (UWW), lung residual volume, and skinfold thickness were measured in the NT. Data were analyzed using repeated measures of ANOVA and Tukey post-hoc test.
Results: We observed that in the CT mean SKBF and Ts decreased (P < 0.05) and R and Xc increased (P < 0.05), compared with those in both NT and HT. However, in the HT both SKBF and Ts increased and R deceased, but Xc remained unchanged relative to the NT. In these subjects, a net change in Ts of 17[degrees]C resulted in a net change in the BIA measure of R of 46 [OMEGA] or 2.5 [OMEGA] per oC. These changes affected the estimate of FFMLUK between CT, NT, and HT, but not the estimate of FFMGuo. Regarding the two BIA equations for estimating FFM, the Guo equation underestimated FFMUWW (P < 0.05) in the CT, NT, and HT, and the Lukaski equation underestimated FFMuww (P < 0.05) only in the CT, compared with that in the UWW technique.
Conclusions: ******t temperature affects Ts and SKBF which in turn influence the BIA measures of R and Xc, especially in the cold ******t temperature; the Guo BIA equation consistently underestimated FFM of young nonobese Chinese women in all temperatures; and the Lukaski equation closely approximates the FFM in the neutral and hot conditions compared with the FFMuww. (C)2000The American College of Sports Medicine
-
06-01-2010, 04:34 PM #20
i had a DEXA in july 2009. i think i took the pics the day before.
5'9 / 145.3lbs
bodyfat 23.2%"The human race is still largely a group of monkeys with slightly better grooming habits. Give them a microscope and and they'll examine their own ****, give them a telescope and they'll go looking for tits."
-
-
06-21-2010, 07:38 PM #21
-
07-18-2010, 08:29 PM #22
- Join Date: Apr 2010
- Location: Washington, District Of Columbia, United States
- Posts: 80
- Rep Power: 180
Wow!
Thanks Emma! It looks like my goal of 20%-22% BF wasn't far off. At the time, I thought that number was high and I would need to readjust as I learned more. Now I see that it's pretty good for my goal and may be more or less based on how I store muscle.
What REALLY surprises me are the classifications based on percentage. For some reason, I thought that I was obese at 31%, which according to what you shared is within the acceptable range. It's pushing it and I need to get it down, which I will, but still within the acceptable range. Cool!
-
08-05-2010, 03:54 PM #23
-
08-05-2010, 07:05 PM #24
-
-
08-20-2010, 06:00 PM #25
-
08-21-2010, 09:16 PM #26
Interesting post, but...
I'm pretty leery of the %BF thing. My trainer busted my chops for my first competition, since the lowest BF I ever had was 26.9% - take a look at that competition photo and tell me if you think that is 27% BF (ie. healthy, bordering on obese)! I went from a DDD to a B+/C and had nothing left anywhere else. I think the %BF may work for young men, but it doesn't seem relevant for women. Even my trainer threw it out the window this time and said simply "we're doing it by eye this time around; forget the measurements!"
And for those of you who are looking... the men really didn't like the 27%BF. Comments included "uhm, uh, have you seen a doctor?", "jayzus, you okay?", "yeah, you need to gain AT LEAST 10 lbs", and my husband's infamous "eeeewww, please don't stay this way".Life is an adventure. Live it!
-
08-21-2010, 09:21 PM #27
-
09-02-2010, 01:19 PM #28
-
-
09-18-2010, 09:32 PM #29
-
09-27-2010, 10:42 AM #30
- Join Date: Dec 2008
- Location: New Jersey, United States
- Age: 56
- Posts: 15,404
- Rep Power: 54295
Going in about an hour to get DEXA, prescribed by the doc. Osteo-diseases in my family, and I was an enudrance athlete in my teens and 20's who had about 2 dozen periods between ages 16 and 30. I'm serious.
So I'll post the results with recent front and back photos for others to reference from.Sheriff John Brown always hated me
For what I don't know
Every time I plant a seed
He said kill them before they grow
Similar Threads
-
Oz's. What are they and how can I measure/compare them.
By kraZi. in forum Teen BodybuildingReplies: 4Last Post: 07-27-2012, 10:59 AM -
how can you tell your body fat has gone down? and what's with the online bf calc?????
By big-n in forum Teen BodybuildingReplies: 10Last Post: 07-17-2011, 10:50 PM -
When and how to measure body fat
By sthompson009 in forum Losing FatReplies: 7Last Post: 03-19-2010, 01:21 PM -
6'0 215lbs and 18.4% body fat, what should i be aiming for?
By Smokey145 in forum Losing FatReplies: 9Last Post: 04-24-2007, 06:13 AM
Bookmarks