Developmental changes in energy expenditure and physical activity in children: evidence for a decline in physical activity in girls before puberty.

Academic Article

Abstract

  • OBJECTIVE: To examine individual changes in energy expenditure and physical activity during prepubertal growth in boys and girls. METHODS: Total energy expenditure (TEE), resting energy expenditure, physical activity-related energy expenditure, reported physical activity, and fat and fat-free mass were measured three times over 5 years in 11 boys (5.3 +/- 0.9 years at baseline) and 11 girls (5.5 +/- 0.9 years at baseline). RESULTS: Four-year increases in fat ( approximately 6 kg) and fat-free mass ( approximately 10 kg) and resting energy expenditure ( approximately 200 kcal/day) were similar in boys and girls. In boys, TEE increased at each measurement year, whereas in girls, there was an initial increase from age 5.5 (1365 +/- 330 kcal/day) to age 6.5 (1815 +/- 392 kcal/day); however, by age 9.5, TEE was reduced significantly (1608 +/- 284 kcal/day) with no change in energy intake. The gender difference in TEE changes over time was explained by a 50% reduction in physical activity (kcal/day and hours/week) in girls between the ages of 6.5 and 9.5. CONCLUSIONS: These data suggest a gender dimorphism in the developmental changes in energy expenditure before adolescence, with a conservation of energy use in girls achieved through a marked reduction in physical activity.
  • Published In

  • Pediatrics  Journal
  • Keywords

  • Basal Metabolism, Child, Child Development, Child, Preschool, Energy Intake, Energy Metabolism, Exercise, Female, Humans, Longitudinal Studies, Male, Physical Exertion, Puberty, Sex Factors
  • Author List

  • Goran MI; Gower BA; Nagy TR; Johnson RK
  • Start Page

  • 887
  • End Page

  • 891
  • Volume

  • 101
  • Issue

  • 5