This article was originally published in The MuscleTalker November 2006 edition
"What is my body fat percentage?"... is a question often asked by budding bodybuilders and fitness enthusiasts. The answer is very hard to gauge without advanced technology or dissection. For most, this is either too expensive or obviously too painful! Full body composition analysis is in the article Assessment of Body Composition in Bodybuilders
The idea of this article is to provide a simple way of measuring skin fold thickness (SFT) at home. Whilst the results may not be 100% accurate, when compared to hydrostatic weighing, it will allow for the monitoring of changes in skin folds, which is an indication of body fat percentage. Hydrostatic weighing will provide a percentage, whilst callipers will provide a skin fold sum, which can be formulated into a percentage score. The sum total is also a useful tool for monitoring progress.
SFT testing has been used in the fitness and medical profession for years and still holds validity even in a world dominated by digital gadgets. Price is also low with most measuring tools starting from as little as £10 in the UK, providing a sliding scale read opposed to a digital display.
SFT testing in its most basic form will follow a one point check. The suprailiac, (above the hip bone) would be the place to monitor skin fold measurements and changes for those using the one point check.
For those wishing to test this area, simply follow the procedure below:
- Find a point around 2-3 cm above the right hip bone
- In a standing position, pinch the site with the thumb and forefinger of the left hand
- Whilst holding the fold place the jaws of the callipers around 1-2cm away
- The pinch is a vertical reading
- Press the callipers with the thumb until the 'click'is heard
- View and record the mm place on the scale
- Remove callipers
- Repeat twice (to the right of the previous measurement)
- Take an average figure from the three readings
- Refer to a standard one point checking chart for estimate of percentage
With subcutaneous fat being the most abundant in the body this method is the primary place where it sits for males and females. Callipers do, however, exclude essential fats, visceral fats and intramuscular fats which should be acknowledged.
The results will be measured in millimetres (mm) this can be charted against percentage to give an appreciation of body fat, but will not provide a definitive result. One point checking is not generally advised for those wishing to gauge an accurate assessment of body fat levels as subcutaneous fat deposits are never equally distributed from person to person. You may hear a bodybuilder say 'my lower back is the last place to come through' meaning their abs are clear but they are holding fat around the lower back.
A three point checking would give a slightly more accurate indication with male sites being chest, abdomen and thigh whilst women would test the suprailiac, tricep and thigh. Again a sum of three figures could be matched to a chart with a rough estimation of body fat percentage or simply used in their original form (mm). With your three readings take the pinches three times for each site and record an average score as you would with the one point check detailed above. The testing of triceps will need to be done by someone else for accuracy. Accuracy is crucial for SFT and having a personal trainer or partner who is both skilled and consistent is essential to monitor changes in you skin fold scores.
Three point testing can be done alone for some, but seven point testing has to be done by a partner due to the location of the additional skin fold sites. The chest, abdominal, suprailiac, midaxillary (around the lat muscle/arm pit area), tricep, thigh and subscapular (below the shoulder bone) will be tested to give a seven-fold sum. Seven-fold sums will give a more accurate assessment of body fat levels than the one or three point checks.
As stated before, some calculators will allow for a fair estimation of body fat but will show an average 1-2% difference between calliper testing and hydrostatic weighing (the gold standard) for the majority of people (Eckerson et al 1998) (based on 3 fold site testing). Although this sounds good news, other studies have shown around 5-6% difference between the equations from the sum of skin folds when compared to hydrostatic weighing.
Sites eight and nine are the bicep and medial calf, and can be added to your skin fold sum for an even more advanced skin fold sum.
Record your location scores and file them for future reference. Initially test each day for the practise and then less frequently as time goes on. Once every 3 days is fine and the test conditions should be replicated as closely as possible. Whilst skin fold testing may not directly equate to accurate body fat percentage measuring it is a great tool, when carried out consistently, to track the changes in subcutaneous body fat levels.ReferenceEckerson JM, et al (1998). Journal of Strength and Conditioning Research. 12 (4): 243-247Leave a comment