Total daily energy expenditure of healthy, free ranging school children

Abstract

This study presents estimates of the energy expenditure of a group of school children. Two data sets were used; one based on the direct measurement of oxygen consumption (VO2) of 36 children while sitting and used to estimate resting energy expenditure (REE) during the day and one based on the indirect estimation of VO2 by the use of heart rate counters and used to estimate energy expenditure while awake (EEA) in 22 children. In all cases nighttime energy expenditure was estimated from tables of basal metabolic rate (BMR). These measures permitted estimated to be made of maintenance energy expenditure (MEE) when MEE=(REE x time out of bed) + (BMR x time in bed); total daily energy expenditure (TDEE) when TDEE=(EEA x time out of bed) + (BMR x time in bed); and energy for activity (EAc) when EAc=(TDEE-MEE). Mean TDEE for boys was 2164 kcal/day and for girls 1716 kcal/day; mean MEE for boys was 1503 kcal/day and for girls 1263 kcal/day; mean EAc for boys was 673 kcal/day and for girls was 434 kcal/day. All differences are statistically significant and, with the exception of EAc, remain so when expressed in terms of lean body mass. Estimates of MEE are close to the theoretical estimates for MEE of 105 kcal/kg.0.75. The lower TDEE in girls suggests that the recommended dietary allowances for energy should be less than for boys.