Patterns of daily energy expenditure in normal and marginally undernourished school-aged Colombian children

Using minute-by-minute heart rate recording, the pattern of energy expenditure (EE), total daily energy expenditure (TDEE) and energy expenditure in activity (EAC) were measured in 132 boys and 110 girls 6-8, 10-12 and 14-16 years of age during ordinary school days. The children were living under economically deprived conditions in Colombia; 70 boys and 59 girls were classified as having marginal malnutrition of sufficient degree to retard growth and sexual maturation. EE, TDEE and EAC increased with age, were in general less in undernourished than control subjects and less in girls than in boys. The age and nutritional group effects were ascribable to differences in lean body mass (LBM). However, the reduced activity in girls was greater than could be accounted for by differences in LBM and are probably the result of cultural pressures. Thus, at the levels of normal activity encountered during school days, the reduced energy expenditure found in undernourished children can be accounted for by differences in body size.