Skinfold Caliper Instructions

Calipers can measure the fat beneath the skin.

Skinfold measurement is the most commonly used way to estimate body fat percentages, according to Georgia State University. Accurate skinfold measurement has a margin of error of 3.5 percent, reports the American Council of Exercise (ACE). Skinfold calipers are easy to use; the technique can be easily mastered. It is believed that about 50 percent of the body's total fat lies under the skin. Taking skinfold measurements at seven points gives a more accurate measure of body fat than does the three-site method.

Things You'll Need

• Skinfold caliper
• Pencil and paper
• Body fat averages chart

Instructions

1. 

   Use a makeup pencil to mark sites for measurement.

   Mark the skinfold sites on the body with a eyebrow pencil, recommends the ACE. The three-site spots differ according to gender.

   If you are taking skinfold-caliper measurements on a man, mark a diagonal line on the chest between the underarm crease and the nipple, a vertical line halfway between the hip and knee on the front of the thigh and a vertical line along the abdomen about an inch away from the belly button.

   If you are taking a woman's measurements, mark a vertical line on the back of the upper arm halfway between the shoulder and elbow, a vertical line on the front of the thigh and a diagonal line along or just above the crest of the hipbone.

   Seven-site skinfold measurements are taken along the chest, on both triceps, on the abdomen, on the hip, under the shoulder bone along the back and on the front of the thigh.

2. 

   Measurement sites differ for men and women if you use the three-site method.

   Grasp the marked area of skin firmly with the thumb and index fingers of one hand. Hold the skinfold calipers perpendicular to the area and place the padded tips on either side of the skinfold about a quarter of an inch from your thumb and index fingers.

3. 

   Measure each site until you get similiar results.

   Release the trigger on the skinfold calipers or read the number on the scale manually. The number should be read to the nearest 0.5 millimeter. Write the number on your piece of paper.

4. 

   Don't take measurements right after exercise.

   Proceed to take measurements at the other skinfold sites. Then retake measurements at each site until you get two measurements that vary under 1 millimeter. The skin must rest at least 15 seconds between multiple measurements.

5. 

   Add the numbers from each site to get a total.

   Add up single measurements taken at each site. Use this sum with the proper chart, either a three-site or seven-site chart, to evaluate body fat.

Tips & Warnings

• The same person should take all the measurements on any one person.

• Skinfold measurement isn't as useful for a very lean or very obese person, warns Georgia State University.

• Don't take skinfold measurements immediately after exercise.

• Skinfold measurements don't take visceral fat into account.

References

• Georgia State University Department of Kinesiology and Health: Body Composition
• American Council of Exercise: Percent Body Fat Calculator