 - Dual Energy X-ray Absorptiometry DXA Scan: A special x-ray of the body called a DXA scan will be done to measure the amount of fat and lean non-fat tissue in the participants body. During the DXA scan, the participant will be asked to lie flat on your back on a table as the scanning machine moves above the participants body. The DXA scan is like an X-ray, and takes about 5-10 minutes. This test is painless and does not involve any needles. 