Body Composition Measurements:
Bionutrition staff are trained to measure height, recumbent length, weight, body circumference, waist-to-hip ratio, and skinfold thickness in the adult and pediatric populations. Special length measurements when height is not appropriate can also be performed.
BIOELECTRICAL IMPEDANCE ANALYSIS (BIA)
Bioelectrical Impedance Analysis (BIA) uses a small electrical current to measure impedance and conductance. Results include body fat, fat-free mass, and total body water. The BIA machine uses electrodes that attach to the hand and foot. The Tanita™ scale requires a standing position without electrodes. The measurement takes approximately 30 seconds to complete. Prior to each measurement an accurate height and weight are obtained. Shoes and socks must be removed and subjects should be fasting (no foods or beverages) and limit physical activity for at least 2 hours prior to the test.
The BOD POD™ uses air displacement plethysmography to measure body density. Results include body fat and fat-free mass as a percent and total kg of body weight. This test is optimal for obese populations with a body weight maximum of 550 lbs.
There is no radiation exposure during a BOD POD™. Subjects are required to wear swimsuits or spandex during the test and must be fasting (no foods or beverages) and limit physical activity for 2 hours prior to the test.
The Dual Energy X-Ray Absorptiometry (DEXA) machine uses a small dose of radiation to determine bone mineral density (BMD) and body composition. Trained staff perform whole body, hip and spine for BMD scans in both adult and pediatric study participants.
A whole body DEXA scan takes approximately 2 minutes and requires the participant to remove all metal (in clothing and jewelry) from the body. Hip and spine scans are shorter in duration. DEXA equipment can only accommodate study participants 350 lbs or less.
DEXA scan results include total and regional (limb, trunk) body composition: bone mineral content and bone mineral density (T-Score and Z-Score) for hip and spine; total mass, fat mass, bone mass, lean mass,and percent body fat. New DEXA software, purchased in 2014, enables the measurement of android and gynoid fat mass.