1. Skinfold Measurements and Girth

2. Skinfold Measurements
Target Population:
Suitable for all populations, difficult to get reliable measurements with individuals who are obese
Validity:
+ or – 3.5%
Can be used as a monitoring device to indicate changes in body composition over time
Reliability:
Can vary from tester to tester depending on their skill and experience
Advantages:
Widely utilized to assess body composition

3. Description of Skinfold Measurement
Triceps
Biceps
Chest
Midaxilla
Subscapular
Abdomen
Suprailium
Thigh
Calf
Estimation of body fat by skinfold thickness
Measurements can range from 3 to 9 different standard anatomical sites around the body

4. Equipment Required
Skinfold Calipers
Flexible Tape Measure

5. YOU MUST SANITIZE EVERYTHING THAT COMES IN CONTACT WITH A CLIENT!
Sanitization
Body Composition measurements require contact with the skin!
Professional Personal Trainers must take the necessary precautions to limit the spread of bacteria and/or viruses.
YOU MUST SANITIZE EVERYTHING THAT COMES IN CONTACT WITH A CLIENT!

6. Hand Washing Should Be Done:
Sanitization
HAND WASHING IS THE MOST EFFECTIVE MEANS OF PREVENTING THE SPREAD OF INFECTION
Hand Washing Should Be Done:
Before and after client contact!

7. Sanitization
Wash hands, utilize gloves, antibacterial gel and/or disposable wipes before, during and after body composition measurements.
Clean and sanitize all equipment. This includes calipers and tape measures.
This also applies to stethoscopes utilized in blood pressure measurements

8. Procedures
Skinfold measurements should be made on dry skin, prior to exercise
The calipers are calibrated with a specific jaw pressure, abuse of the calipers can leave them useless due to inaccuracy
Fat compresses, thus it is essential that you rotate through measurement sites which allows time for skin to regain normal thickness
It takes experience before sufficient accuracy of measurements occurs

9. Procedures
All measurements should be made on the right side of the body (for consistency)
Grasp the skin firmly with the thumb and index finger to form a fold of skin and subcutaneous fat
Place the caliper perpendicular to the fold .5 to 1 inch away from the thumb and index finger
Release the caliper grip
Pinch should be maintained with thumb and index finger while reading the caliper

10. Procedures
6. Wait 1 to 2 seconds (not longer) before reading caliper
7. Read the dial on the caliper to the nearest 0.5 mm
8. Obtain one measurement from each site, and repeat all test sites for a second trial

11. Procedures If the two measurements are within 1 to
2 mm take the average of the two
10. If the two measurements are not within
1 to 2 mm take two more additional
measurements and average the
two (rotate through the sites)

12. Triceps Triceps: Use a tape measure
Arm held freely to the side of the body
Measure halfway between the acromion (shoulder) and olecranon processes (elbow)
Grasp a vertical fold of skin on the posterior surface of the arm (over the triceps muscle)
If you are unsure if you have pinched only skin and no underlying muscle tissue, ask the subject to flex the muscle while you pinch.
Triceps

13. Biceps Use a tape measure
Arm held freely to the side of the body with the palm supinated
Measure halfway between the acromion (shoulder) and radius
Take a vertical fold of skin on the anterior surface of the arm (over the biceps muscle)
If you are unsure if you have pinched only skin and no underlying muscle tissue, ask the subject to flex the muscle while you pinch.
Biceps

14. Chest:
Measure mid-way between the anterior axillary fold (underarm) and nipple
Take a diagonal fold, with the long axis of the caliper directed towards the nipple of the chest

15. Midaxilla:
Measure from the midaxilla (middle of armpit) at the level of the xiphoid process of the sternum
Take a vertical fold

16. Subscapula:
A diagonal fold taken at a 45 degree angle; 1 to 2 cm below the inferior angle of the scapula (bottom point of the scapula)
If there is difficulty finding this landmark, get the subject to reach behind their back with their right arm, while feeling for the movement of the scapula
On females it is sometimes difficult to take this measure and maintain modesty, and also the bra-strap may often obstruct this site.

17. Abdomen:
Measure 1 inch to the right of the umbilicus (belly button)
Take a vertical fold
Do not place the caliper or fingers inside the navel

18. Suprailium:
Measure from the axilla (armpit) to above the crest of the ilium
Take a diagonal fold at a 45 degree angle above the crest of the ilium

19. Stand with the weight on the back foot
Thigh:
Measure the mid-point of the anterior (front) surface of the thigh, midway between the hip and knee joints
Take a vertical fold 
Stand with the weight on the back foot

20. Calf:
Take a vertical fold at the maximum circumference of the calf on the midline of its medial border
The subject should place their foot on a chair or box so that the knee is at approximately 90 degrees

21. Results
There are hundreds of equations available for converting skinfold measurements to a percent body fat
It is best to use a formula that is based on a population sample that most closely resembles the person who is measured
You can use the sum of several sites to monitor and compare body fat measures
Go to
to find out your body fat percentage

22. Table of general guidelines for using total sum (in millimeters) of the seven skinfold sites: triceps, biceps, subscapula, suprailium, abdomen, thigh, calf
Excellent
Good
Average
Below Average
Poor
Typical
Male
60-80
81-90
91-110
150 +
Female
70-90
91-100
Athletic
40-60
61-80
81-100
130 +
50-70
71-85
86-110

23. Durnin-Womersley Formula
Biceps, Triceps, Subscapula, and Suprailium
Add the totals of the four sites and then find the gender and age categories for the body composition in the table provided or go to
to find out your body fat percentage

24. Body Fat Percentage Ranges by The American Council on Exercise
Classification
Women (% fat)
Men (% fat)
Essential Fat
10-12%
2-4%
Athletes
14-20%
6-13%
Fitness
21-24%
14-17%
Acceptable
25-31%
18-25%
Obese
32% plus
25% plus
   

25. Circumference
When measuring, you need to make sure the tape is not too tight or too loose, is lying flat on the skin, and with the tape horizontal

26. Circumference Neck: Forearm: Across the Adam’s apple
The subject holds the arm out with the palm supinated
Maximum girth of forearm

27. Circumference Measurements
Biceps Relaxed:
Measure at the maximal circumference of the biceps, measure with the palm supinated
Biceps Contracted:
Arm is out to the side at a 90 degree angle and elbow is flexed
Fist clenched; maximally contract biceps
Largest circumference is measured

28. Circumference Upper Chest: Lower Chest:
Taken at the level of the middle of the sternum with the tape passing under the arms
Measurement taken at the end of a normal expiration
Lower Chest:
Across the nipple line

29. Circumference Abdomen: Waist: Level of umbilicus (belly button)
Narrowest part of waist below the rib cage and just above the top of the hipbones.

30. Circumference
Hips:
With feet together, measure circumference at the widest portion of the buttocks
Thighs:
Measure 10 inches above the top of the patella (maximal girth of thigh below gluteal fold)
Calf:
The subject stands erect with their weight evenly distributed on both feet and legs slightly apart
Measure at the maximal circumference between the ankle and the knee