How to Calculate Body Fat Percentage from Skinfold

A skinfold test is used for monitoring changes in body composition over time and to estimate body fat. The test can be used on all populations including children, although reliable readings may be difficult to obtain on obese people. The procedure consists of a trained tester pinching the skin and using skinfold calipers to measure the thickness of skin and adipose tissue (fat). Scales, such as the Durmin and Wormersley or the Slaughter formula, may be used to translate the caliper readings. Learn how to calculate body fat percentage from skinfold at home to monitor body changes if you are an athlete preparing for competition or if you are dieting and want to keep track of your progress.

Steps

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    Purchase a skinfold caliper. You can choose an inexpensive home set or the pricier research-grade calipers.
    • Skinfold calipers can be found online, at health supply stores, and at pharmacies.
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    Determine the test sites. Most tests are done on the right side of the body. However, scars, injuries, or amputation may necessitate testing on the left side.
    • The 7 main skin fold test sites include triceps, biceps, subscapular, supraspinale, abdominal, thigh, and calf.
    • An optional testing site may include the iliac crest.
    • Select several sites to test and monitor over time.
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    Pinch a skinfold with the thumb and index finger.
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    Place the measuring tips of the calipers at a right angle .39 to .79 inches (1 to 2 cm) below your fingers. Wait 2 seconds.
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    Note and record the reading.
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    Release the calipers.
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    Wait 1 to 2 seconds, and repeat the testing procedure 2 more times.
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    Add the 3 measurements, and obtain the average by dividing the sum by 3.
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    Make note of the average reading.
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    Move to the remaining test sites, and take 3 more readings at each spot.
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    Record the average of the readings for each test site.
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    Use an approved skinfold test scale to interpret the results of the test.
    • In general, a normal male receives an excellent rating with a score of 80 or lower and a poor rating with a score of 150 or higher.
    • A normal female receives an excellent rating with a score of 90 or lower and a poor rating with a score of 150 or higher.
    • The scores of good, average, and below average fall in between these 2 ratings.
    • Some scales may convert skinfold caliper readings to a percentage of body fat. This is not recommended due to the high possibility of errors.

Tips

  • Test the same sites in the exact same way each time for reliable results.
  • Keep a log of the measurements to help in monitoring changes.
  • Test regularly to adequately monitor body composition changes.
  • Keep the calipers calibrated to ensure accurate measurements.
  • Skin fold testing accreditation courses are available through the International Society for the Advancement of Kinanthropometry (ISAK).

Warnings

  • Slight variations in measurements can lead to large discrepancies in results.

Things You'll Need

  • Skinfold caliper
  • Pencil and pad for recording

Article Info

Categories: Losing Weight