Comparison of heart rate monitoring combined with indirect calorimetry and the doubly labelled water (²H₂¹⁸O) method for the measurement of energy expenditure in children

The aim of the present study was to compare data on 24-h energy expenditure (EE24 h) in nine boys and ten girls (mean age 9.3 and 8.1 years, respectively) by heart rates (f c) combined with energy expenditure obtained from a 1-day stay in an indirect calorimeter (EEcal) and a 2-week period of normal living using the doubly labelled water method (EEdlw). Individual calibration curves were derived fromf c and oxygen uptake measured during sleep (in the calorimeter), standing and walking on a treadmill. An estimation of energy expenditure based on 24-hf c, monitoring (EEf c) was made during the stay in the calorimeter and on a normal school-day. Mean results showed an overestimation in EE fc compared to EEcal and EEdlw of 10.4% and 12.3% respectively, varying from 6.3% to 16.2%. These results confirmed earlier observations in adults that for a group thef c method overestimates EE24 h by about 10%.