Year of Publication


Degree Name

Master of Science in Nutrition and Food Systems (MSNFS)

Document Type

Master's Thesis


Agriculture, Food and Environment


Dietetics and Human Nutrition

First Advisor

Dr. Kyle Flack


Background: Body composition measures include fat mass (FM), fat free mass (FFM), and percent body fat (%BF), which are markers of health status and disease risk. Accurate body composition assessment is needed to evaluate an individual’s health and the efficacy of treatment strategies. Objective: Compare body composition estimates obtained from the Norland DXA, BodPod®, and iDXA before and after a 12-week exercise intervention. Subjects/setting: Overweight to obese (BMI 25–35 kg/m2) sedentary men and women (n=30) aged 18 to 40 years were recruited from central KY. Main outcome measure: Agreement in FM, FFM, and %BF between Norland DXA, iDXA, and BodPod®. Statistical analysis: Bland Altman plots evaluated mean bias and limits of agreement between iDXA vs Norland DXA, BodPod® vs Norland, and BodPod® vs iDXA. T-tests determined if each mean bias was different from zero. Results: Compared to the iDXA, Norland DXA overestimated BF% and FM at baseline and post intervention (P < 0.01), without differences in FFM (P > 0.05). The BodPod® underestimated BF% and FM and overestimated FFM compared to both DXA machines(all P < 0.01). Conclusion: The Norland and iDXA produce different measures of FM but similar measures of FFM. As well, the BodPod® measures FM and FFM differently than either DXA machine.

Digital Object Identifier (DOI)