Effects of daily activities on dual-energy X-ray absorptiometry measurements of body composition in active people

Purpose: Dual-energy x-ray absorptiometry (DXA) is becoming a popular tool to measure body composition in athletes, owing to its ease of operation and comprehensive analysis of body composition. This study represents the first systematic investigation of the reliability of DXA measurements of body composition in trained individuals and includes measurements of daily variability as well as the specific effect of the intake of a meal. Methods: Physically active young adults (15 females, 16 males) underwent five whole-body DXA scans during a 2-d period: in the morning after an overnight fast, 5 min later after repositioning on the scanning bed, 8 h later after usual daily activities, and the next morning before and 30 min after consumption of a simple breakfast.