Answer:
1. Skinfold Calipers
Skinfold measurements have been used to estimate body fat for over 50 years (1Trusted Source).
Skinfold calipers measure the thickness of your subcutaneous fat — the fat underneath the skin — at certain body locations.
Measurements are taken at either 3 or 7 different sites on the body. The specific sites used vary in men and women.
2. Dual-Energy X-ray Absorptiometry (DXA)
As the name implies, DXA uses X-rays of two different energies to estimate your body fat percentage (6Trusted Source).
During a DXA scan, you lie on your back for approximately 10 minutes while an X-ray scans over you.
The amount of radiation from a DXA scan is very low. It’s about the same amount you receive during three hours of your normal life (7).
3. Hydrostatic Weighing
This method, also known as underwater weighing or hydrodensitometry, estimates your body composition based on its density (9Trusted Source).
This technique weighs you while submerged under water after exhaling as much air as possible from your lungs.
You are also weighed while you are on dry land, and the amount of air left in your lungs after you exhale is estimated or measured.
