Assessing Resting Metabolic Rate in Overweight and Obese Adolescents With a Portable Indirect Calorimeter: A Pilot Study for Validation and Reliability.
BACKGROUND
Indirect calorimetry measured via the traditional indirect calorimeter is considered the "gold standard" for determining resting metabolic rate (RMR). Portable devices for assessing RMR are a less expensive option for measuring RMR in the clinical setting. This pilot study tested the reliability and validity of a portable device for measuring RMR, specifically in overweight and obese adolescents.


METHODS
Participants aged 17-19 years (n = 19) and ≥85th percentile on the Centers for Disease Control and Prevention body mass index growth curves for age and sex were recruited from a university campus. Participants completed testing on a traditional indirect calorimeter and a portable indirect calorimeter in a randomized order on 2 separate testing days.


RESULTS
A paired samples t test comparing the means of the portable device and the traditional indirect calorimeter found no significant difference (P = .22). The test-retest intraclass correlation coefficient for assessing RMR was 0.91, indicating reliability of the portable indirect calorimeter. Compared with measured RMR, the Mifflin-St Jeor equation demonstrated 37% accuracy, and the Molnar equation demonstrated 57% accuracy.


CONCLUSIONS
This pilot study found portable indirect calorimetry to be reliable and valid for assessing RMR in an overweight and obese adolescent population. In addition, this study indicates that portable indirect calorimetry may be an acceptable option for assessing RMR in this population compared with the traditional indirect calorimeter or predictive equations.
Department of Nutrition, Georgia State University, Atlanta, Georgia shenes@gsu.edu.
Sarah T
ST
Henes
Department of Nutrition, Georgia State University, Atlanta, Georgia Children's Health Care of Atlanta, Aerodigestive Clinic, Atlanta, Georgia.
Abby
A
Johnson
Department of Nutrition, Georgia State University, Atlanta, Georgia.
Marti
M
Toner
School of Nursing, Georgia State University, Atlanta, Georgia.
Kamille
K
Mamaril
School of Nursing, Georgia State University, Atlanta, Georgia.
Maya
M
Kelkar
Department of Mathematics and Statistics, Georgia State University, Atlanta, Georgia.
Yuanhui
Y
Xiao
Department of Physical Therapy, Georgia State University. Atlanta, Georgia. Dr Xiao's current affiliation is the Department of Mathematics and Statistics, Mississippi State University, Starkville, Mississippi.
Gordon L
GL
Warren
D000293:Adolescent; D000328:Adult; D001481:Basal Metabolism / Q000502:physiology*; D002153:Calorimetry, Indirect / Q000379:methods* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D050177:Overweight / Q000503:physiopathology*; D063766:Pediatric Obesity / Q000503:physiopathology; D010865:Pilot Projects; D015203:Reproducibility of Results; D055815:Young Adult
adolescent; energy expenditure; energy metabolism; indirect calorimetry; obesity; resting energy expenditure