Body composition can be expressed as the relative percentage of the body that is fat mass and fat-free mass. The DXA scan is a precise way to distinguish between your fat-free and fat mass along with bone density. The DXA scan can also distinguish the percent of fat located around the abdomen and hips. Abdominal fat is more metabolically active and is associated with higher rates of the metabolic syndrome which includes diabetes, high blood pressure, high cholesterol, coronary artery disease and premature death.
Popular assessments of body composition include skin anthropoloy measurements (skin folds), BMI, hydrodensitometry, impedence scales, and the DXA. The DXA has become the "gold standard" for body composition over the past few years.
How it works:
The DXA scanner sends a thin x-ray beam through the body part being examined. Digital detectors receive the non absorbed x-ray beam and help to provide precise calculations of bone mineral density, bone mineral content values, lean and fat tissue mass, and fat percentages. Routinely the bone density exam is performed of the lower spine and both hips to evaluate for osteopenia, and osteoporosis. The body composition measurements are performed over the entire body. These measurements are more precise and look beyond just weight, but at the distribution of lean and fat tissue composition. The distribution includes total body, trunk, arms, legs, and pelvis.
The process takes about 8-10 minutes. Each person receives a detailed report which is discussed and interpreted by the Exercise Physiologist.