title: Energy expenditure in African American and white boys and girls in a 2-y follow-up of the Baton Rouge Children's Study.
abstract: BACKGROUND
  Previously reported race and sex differences in energy expenditure (EE) may play a role in body fat gain.
  
  
  OBJECTIVE
  The purpose of the study was to determine the relations between race, sex, Tanner stage, and EE.
  
  
  METHODS
  We conducted a 2-y follow-up study of EE in 114 African American (AA) and white girls and boys aged 12.7 +/- 0.1 y ( +/- SE), who were stratified as obese or lean and were part of the Baton Rouge Children's Study. Total daily EE (TDEE) was measured by using doubly labeled water. Resting metabolic rate (RMR) and thermic effect of food were measured by using indirect calorimetry.
  
  
  RESULTS
  White children had significantly higher TDEE and RMR than did AA children when fat-free mass was considered. Boys had significantly higher TDEE and RMR than did girls, even after adjustment for differences in size. TDEE and RMR were significantly higher in obese children, as a result of their greater fat-free mass and body fat, than in lean children. Activity-related EE did not differ significantly between obese and lean children. There was a strong relation between initial and 2-y TDEE and RMR. There was a significant decrease in activity-related EE in both racial groups. AA children had significantly more lean limb mass than did white children.
  
  
  CONCLUSIONS
  Average TDEE did not change over 2 y, but RMR increased significantly, and activity-related EE decreased significantly. Differences in trunk and limb lean mass of white and AA children may explain some of the ethnic differences in EE. The decrease in physical activity over 2 y may contribute to the risk of obesity.
authors.affiliation: Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA. delanyjp@pbrc.edu
authors.forename: James P
authors.initials: JP
authors.lastname: DeLany
authors.forename: George A
authors.initials: GA
authors.lastname: Bray
authors.forename: David W
authors.initials: DW
authors.lastname: Harsha
authors.forename: Julia
authors.initials: J
authors.lastname: Volaufova
mesh_terms: D015502:Absorptiometry, Photon; D001481:Basal Metabolism; D044383:Black People; D001823:Body Composition; D002153:Calorimetry, Indirect; D002648:Child; D004734:Energy Metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008145:Louisiana; D008297:Male; D009765:Obesity / Q000378:metabolism*; D017678:Sex Distribution; D044465:White People; D001741:Black or African American