Which method estimates body fat percentage based on body volume and air displacement?

The method that estimates body fat percentage based on body volume and air displacement is air displacement plethysmography. This technique involves measuring the amount of air that occupies a person's body volume inside a sealed chamber, which allows for an accurate calculation of body density. Once body density is established, it can be used alongside variables like age, sex, and ethnicity in formulas to estimate body fat percentage.

Air displacement plethysmography is particularly valued for its precision and non-invasive nature, making it an excellent choice for assessing body composition in various populations. It effectively measures changes in body volume by detecting variations in air pressure as the subject enters a chamber designed to calculate body volume.

In contrast, hydrostatic weighing requires submersion in water and can be less comfortable for some individuals. Skinfold measurement relies on calipers to assess subcutaneous fat at specific sites, which can introduce variability based on the technician's skill. The waist-to-hip ratio is a more simplified measure of fat distribution rather than body fat percentage. Hence, air displacement plethysmography is the most fitting choice among these methods for estimating body fat percentage directly from body volume and air displacement.