Abstract
We assessed activity energy expenditure (AEE) in Mexican-American (MA) and European-American (EA) children. Total energy expenditure (TEE) was measured using the doubly-labeled water method; AEE was calculated as the difference between TEE and resting EE (REE), and physical activity level (PAL) was calculated as TEE/REE. Groups were comparable for age, sex and body mass index (BMI). REE did not differ between groups. The boys did not differ in TEE, AEE, or PAL (MA vs. EA, respectively: TEE, 7.9±1.5 vs. 7.5±0.9 MJ.d−1; AEE: 64.9±24.7 vs. 65.3±22.3 kJ.kg−1.d−1; PAL: 1.57±0.18 vs. 1.58±0.19 kJ.kg−1.d−1). MA girls had lower TEE, AEE, and PAL than EA girls (TEE: 6.8±0.9 vs. 8.1±0.8 MJ.d−1; AEE, 37.3±15.9 vs. 64.9±24.7 kJ.kg−1.d−1; PAL, 1.40±0.12 vs. 1.57±0.18; P <0.005). Results suggest that these MA girls were expending less energy than EA children of comparable body size due to a reduced activity energy expenditure.
Acknowledgements
Mr. Tim Shriver from the Stable Isotope Core Laboratory, University of Wisconsin, Madison, Wisconsin is thanked for the analysis of the DLW samples and the staffs of the Maywood and Bethesda clinics are thanked for their assistance with the sample collections. J.A.Y. is a Commissioned Officer in the US Public Health Service.
This study was funded by: the National Institutes of Health R01 DK30031 (D.A.S.); the Intramural Research Program of the National Institutes of Health, Grant Z01-HD-00641 (NICHD) (J.A.Y.) supplemental funding from the National Center for Minority Health and Health Disparities (J.A.Y.); and internal support from Loyola University Stritch School of Medicine (A.L.).