The body fat skinfold test is performed with a skinfold caliper, a grasping tool that measures the amount of subcutaneous fat at various spots on the body. The caliper measures the distance between the two points of skin grasped within the pincers and reports a skinfold thickness in millimeters. Three skinfold sites are used to calculate body density and body fat percentage. In men, the three sites are chest, thigh and abdomen. In women, the three sites are triceps, thigh and suprailiac.
Identify Skinfold Measurement Sites
Step 1
Use the marking pen to make an X at the triceps site on the back of the arm over the triceps muscle, midway between the elbow and the bony protrusion of the shoulder called the acromion process.
Step 2
Make an X at the abdomen site, 3 cm to the right of the belly button and 1 cm below it.
Step 3
Mark an X at the thigh site on the front of the leg, midway between the hip and knee joints.
Step 4
Use the marking pen to make an X at the suprailiac site just in front of the crest of your hip bone.
Step 5
Mark the chest with an X midway between the front crease of your underarm and your nipple.
Skinfold Measurement (Men)
Step 1
Use your thumb and index finger to pinch a diagonal piece of skin over the previously marked X. This is the chest skinfold site.
Step 2
Approach the skinfold site perpendicularly with the calipers open.
Step 3
Release the calipers once they are surrounding the skinfold so that the pads gently pinch the skinfold about 1/4 inch from your fingers for two seconds.
Step 4
Read the measurement on the caliper dial. Record this as the first measurement for the chest site.
Step 5
Repeat steps 1 through 4 for the thigh and abdomen sites. These sites will be measured vertically rather than diagonally.
Skinfold Measurement (Women)
Step 1
Use your thumb and index finger to pinch a diagonal piece of skin over the previously marked X. This is the suprailiac site.
Step 2
Approach the skinfold site perpendicularly with the calipers open.
Step 3
Release the calipers once they are surrounding the skinfold so that the pads gently pinch the skinfold about 1/4 inch from your fingers for two seconds.
Step 4
Read the measurement on the caliper dial. Record this as the first measurement for the suprailiac site.
Step 5
Repeat steps 1 through 4 for the thigh and triceps sites. These sites should be measured vertically rather than diagonally.
Calculating Body Density and Body Fat Percentage (Men)
Step 1
Add up the measurements of the three skinfold sites.
Step 2
Plug the sum into the following equation to get body density:
Body density = 1.109380 - 0.0008267(SKINFOLD SUM) + 0.0000016(SKINFOLD SUM)^2 - 0.0002574(YOUR AGE)
Step 3
Use the result of step 2 to determine body fat percentage with the following equation:
Body fat percentage = [(4.95/body density) - 4.50] x 100
Calculating Body Density and Body Fat Percentage (Women)
Step 1
Add up the measurements of the three skinfold sites.
Step 2
Plug the sum into the following equation to get body density:
Body density = 1.0994921 - 0.0009929(SKINFOLD SUM) + 0.0000023(SKINFOLD SUM)^2 - 0.0001392(YOUR AGE)
Step 3
Use the result of step 2 to determine body fat percentage with the following equation:
Body fat percentage = [(5.01/body density) - 4.57] x 100
Tips and Warnings
- All skinfold measurements should be performed on the right side. It can be very difficult to accurately measure your own skinfolds, so ask a friend for help. For the most accurate result, perform three rounds of skinfold measurements and find the average for each site. For easier body density and body fat percentage calculations, use an online calculator (see Resources).
- Skinfold measurement is best performed by a skilled and experienced fitness technician or exercise physiologist. Amateur measurements can be highly variable and inaccurate.
Things You'll Need
- Skinfold caliper
- Skin-safe marking pen
- Calculator
References
- "Essentials of Exercise Physiology"; William D. McArdle, Ph.D, M.Ed., Frank L. Katch, Ph.D, Victor I. Katch, Ph.D.; 2006
- American Council on Fitness: Percent Body Fat Calculator, Skinfold Method
Member Comments