What is the only authorized method for estimating body fat as per AR 600-9?

The correct answer emphasizes that the circumference-based tape method is the only authorized method for estimating body fat according to AR 600-9. This regulation provides guidelines for assessing body weight and composition within the military, ensuring uniformity and compliance across various units.

The circumference-based tape method involves measuring specific body sites such as the neck and waist, and it calculates body fat based on those measurements. This approach is favored for its practicality, ease of use, and effectiveness in a military setting where quick assessments may be needed without the use of complex equipment.

Other methods, while potentially useful in different contexts, are not endorsed by this specific regulation. For instance, the body mass index method relies solely on height and weight, not directly measuring body fat. Skinfold measurements require calipers and specific techniques that can introduce variability and may not be as accessible. Bioelectrical impedance analysis, while accurate, involves electronic equipment that may not be readily available in all environments, which impacts its operational feasibility in a military context. Thus, the regulation supports only the circumference-based tape method for consistency and compliance across the force.