§ 01
Body Composition
Clinical fitness assessment

3-Site Skinfold (Body Fat %)

Estimate body fat percentage using skinfold callipers at 3 anatomical sites.

Equipment

Skinfold callipers (e.g. Harpenden, Lange, or Slim Guide).

The protocol
  1. 01Identify the correct sites — Males: chest, abdomen, thigh. Females: triceps, suprailiac, thigh.
  2. 02Mark each site with a pen on the RIGHT side of the body.
  3. 03Grasp the skinfold firmly between thumb and forefinger, pulling it away from the muscle.
  4. 04Apply the calliper jaws 1 cm below the fingers, perpendicular to the fold.
  5. 05Wait 2 seconds for the reading to stabilise, then record.
  6. 06Take 2 measurements at each site and use the average.
  7. 07If measurements differ by more than 2 mm, take a third and use the median.
What to watch for
  • Grabbing muscle with the fat fold — pinch only skin and subcutaneous fat.
  • Not waiting 2 seconds — the reading continues to decrease as the calliper compresses.
  • Measuring on the left side instead of the right (convention is right side).
  • Callipers not calibrated or sprung correctly.
Normative scoring

Body fat % varies by age and gender. Men: Essential 2-5%, Athletic 6-13%, Fitness 14-17%, Acceptable 18-24%, Obese ≥25%. Women: Essential 10-13%, Athletic 14-20%, Fitness 21-24%, Acceptable 25-31%, Obese ≥32%.

Run it with GainPT

Run this test with branded client reports.

GainPT scores 3-Site Skinfold (Body Fat %) against published normative data and turns it into a clean, GainPT-branded PDF your client keeps. All 47 clinical tests, unlimited retests — free to start, no card required.