Publish Date: Sunday, May 01, 2005
1571 Board #26 9:30 AM - 11:00 AM Medicine & Science in Sports & Exercise: Volume 37(5) Supplement May 2005 p S299-S300. Assessment of body fat percentage is desirable to identify health risk associated with obesity. There are few studies that have compared the assessments of body fat between air displacement plethysmography and DEXA, particularly related to age and gender differences. PURPOSE: To determine if body fat percentage estimates differ depending on age and/or gender between two measurement methods. METHODS: Sixty subjects were studied: 15 men and 15 women 22-35 years and 15 men and 15 women, 55-80 years. None of the subjects competed in athletics or high-level exercise training in the last year. Each subject was measured with air displacement plethysmography (BOD POD, Life Measurements Instrument, Concord, CA) and dual-energy x-ray absorptiometry (DEXA, General Electric Medical Systems, Lunar Prodigy, Madison, WI). Standard calibration and testing procedures were used for both methods. Both body composition methods were administered at least twice to evaluate reliability and were repeated a third time if the measures differed by > 2%. Differences between methods for the age groups and gender were analyzed using ANOVA and reliability comparisons between the body composition methods were evaluated with correlation coefficients. RESULTS: Using data for all subjects, DEXA (r = .996) and BOD POD (r = .985) both showed good reliability. However, in younger females the reliability of the BOD POD (r = .91) was lower. Eight of the 60 subjects required a third trial for the BOD POD, whereas all repeated DEXA measures were consistent. The deviation between trials 1 and 2 for the DEXA (.6%) was significantly less than that in the BOD POD (1.5%). Significant interactions between the body composition method and age group were found. Mean body fat percentage in the younger group was higher in the DEXA (24.1 + 1.1%) than the B OD POD (23.0+1.3 %) however, in the older group was found to be lower in the DEXA (33.9 + 1.1%) than the BOD POD (37.2 + 1.3%). CONCLUSION: Although both DEXA and BOD POD measures were reliable, repeated DEXA measures were more consistent and less deviant. BOD POD estimates of body fat percentage were lower for younger subjects, yet higher for older subjects compared to DEXA measurements. ©2005 The American College of Sports Medicine
Presentation Detail
Author
Co-Presenter(s)
Kathryn M. Nowak
Location
Nashville, TN
