Time to achieve steady state for an accurate assessment of resting energy expenditure in adolescents with healthy weight and obesity: A cross-sectional study

Abstract

Objective: The present study investigated the time needed to achieve a steady state for an accurate assessment of resting energy expenditure (REE) in adolescents with healthy weight and obesity. Materials and methods: Thirty adolescents aged 12-17 years were assigned to a group with healthy weight (GHW; n = 12, body mass index [BMI] 22.5 ± 3.6 kg/m 2 ) and another group with obesity (GO; n = 18, BMI 34.1 ± 5.2 kg/m 2 ). Participants underwent test-retest reliability of REE assessment as follows: a) 24 h of abstention from physical exercise, soft drinks, or caffeine; b) fasting for ~12 h; c) acclimation period of 10 min; d) 30-min assessment in a supine position. Results and discussion: A significant change occurred during the 30 min in REE. Significant differences existed between consecutive means until the 20 th and 25 th min for the GHW and GO, respectively. Although significant differences between trials 1 and 2 were detected during the first 5-10 min of assessment, the REE for each 5-min time point exhibited high test-retest reliability across trials in both groups (intraclass correlation coefficients range 0.79-0.99). Conclusion: The following recommendations are provided to promote accurate assessment of REE among adolescents: a) initiate the REE assessment with 10 min of acclimation to decrease restlessness; b) determine REE for a minimum of 20 min if healthy weight and 25 min if obesity; c) determine REE for a further 5 min, with the average of this last 5 min of REE data being regarded as the REE.

Comparison of energy expenditure measurements by a new basic respiratory room vs. classical ventilated hood

“…This way, subjects could remain in the same resting facilities and environmental conditions. Momentary EE was assessed after 3 h of fasting as approximation of resting EE (REE) [ 17 ]. Assessment of momentary EE by ventilated hood was identical for P1 and P2 (Fig.…”

“…The measurement with ventilated hood lasted 30 min and data were provided every 5 s. Only data of the last 20 min were used to ascertain a balanced recording of gas exchange rates ( O 2 and CO 2 ) as fluctuations are often seen in the beginning of the measurement due to a slow decrease towards a resting level. From sitting or standing to resting in supine position, there is a decrease in EE which typically takes 10 min to achieve a steady state [ 17 , 18 ]. The Weir equation (Weir, 1949) was used to convert O 2 and CO 2 to EE values.…”

Effect of a Supervised Exercise Program on Overweight and Obese Adolescents in the School Environment: A Pretest-Posttest Design

“…The results indicated that the prevalence of overweight children increased by 103% and indicators of abdominal obesity increased by 153% during the study period. 21 In addition, a study found a prevalence of 13.6% overweight, 5.1% obesity, and 4.0% severe obesity among children in the state of Acre, Brazil. 22 There are several treatments for obesity and overweight, and physical exercise is one of the key approaches.…”