Understanding Body Fat Percentage
Body fat percentage is a measure of fitness level, as it is the only body measurement which directly calculates a person's relative body composition without regard to height or weight. Your body needs a certain amount of fat to function properly—this is known as essential fat.
Calculation Methods
The U.S. Navy Method: Developed by the Naval Health Research Center, this method estimates body fat using basic tape measurements. It relies on the circumference of the waist, neck, and (for women) hips, along with height. While not as precise as clinical methods, it is highly accessible and provides a good estimate for tracking changes over time.
The Jackson-Pollock 3-Site Skinfold Method: This method involves pinching the skin and subcutaneous fat with calipers at three specific points on the body. The sites differ for men (Chest, Abdomen, Thigh) and women (Triceps, Suprailiac, Thigh). These measurements are used to estimate body density, which is then converted into a body fat percentage using the Siri equation. This method is generally considered more accurate than circumference measurements if performed correctly.
Body Fat Categories (American Council on Exercise)
- Essential Fat: 2-5% (Men), 10-13% (Women)
- Athletes: 6-13% (Men), 14-20% (Women)
- Fitness: 14-17% (Men), 21-24% (Women)
- Average: 18-24% (Men), 25-31% (Women)
- Obese: 25%+ (Men), 32%+ (Women)