Which technique requires the use of a specific machine known as a DEXA?

Dual-Energy X-ray Absorptiometry (DEXA) is a specialized imaging technology that measures bone mineral density and body composition, including fat mass and lean mass, using low-energy X-rays. This technique is highly accurate and provides detailed information about the distribution of body fat and lean tissue, making it particularly useful in both clinical and research settings.

The DEXA scan involves the patient lying on a table while the machine passes over them, generating images that are analyzed to determine body composition. This method stands out from others due to its precision and its ability to differentiate between different types of tissues, such as fat and muscle, in various regions of the body.

Other methods listed, while also measuring body composition, do not require the specific DEXA machine. Hydrostatic weighing relies on water displacement, bioelectrical impedance analysis involves sending a small electrical current through the body, and skinfold measurements use calipers to assess subcutaneous fat thickness at specific sites on the body. Each of these methods operates on different principles and tools, making DEXA unique in its requirements and capabilities.