Energy expenditure and physical activity in recovering malnourished infants.

Background. Malnourished infants are small for age and weight. Objectives. Determine profiles in 24-hour energy metabolism in recovering malnourished infants and compare to similarly aged healthy controls. Methods. 10 malnourished infants (58.1 +/- 5.9 cm, 7.7 +/- 5.6 months) were healthy prior to spending 22 hours in the Enhanced Metabolic Testing Activity Chamber for measurement of EE (kcal/min), sleeping metabolic rate (SMR; kcal/min), respiratory quotient (RQ; VCO(2)/VO(2)), and physical activity (PA; oscillations in wt/min/kg body weight). Metabolic data were extrapolated to 24 hours (kcal/kg/d). Energy intake (kcal/kg/d) and the proportions (%) of carbohydrate, protein, and fat were calculated. Anthropometrics for malnourished infants were obtained. Statistical differences (P < .05) between groups were determined (SPSS, version 13). Results. In comparison to controls, malnourished infants were lighter (4.1 +/- 1.2 versus 7.3 +/- 0.8 kg; P < .05), had less body fat % (10.3 +/- 7.6 versus 25.7 +/- 2.5), and lower BMI (12.0 +/- 1.7 versus 15.5 +/- 1.5; P < .05). In contrast, they had greater energy intake (142.7 +/- 14.6 versus 85.1 +/- 25.8; P < .05) with a greater percentage of carbohydrates (55.1 +/- 3.9 versus 47.2 +/- 5.2; P < .05). However, malnourished infants had greater 24-hour EE (101.3 +/- 20.1 versus 78.6 +/- 8.4; P < .05), SMR (92.6 +/- 17.1 versus 65.0 +/- 3.9; P < .05), and RQ (1.00 +/- 0.13 versus 0.86 +/- 0.08; P < .05) along with a lower amount of PA (2.3 +/- 0.94 versus 4.0 +/- 1.5; P < .05). Conclusions. Malnourished infants require more energy, possibly for growth.