Impact of methods for data selection on the day-to-day reproducibility of resting metabolic rate assessed with four different metabolic carts

• Published in: Nutrition, metabolism, and cardiovascular diseases metabolism, and cardiovascular diseases, 2023-11, Vol.33 (11), p.2179-2188
• Main Authors: Alcantara, J.M.A., Jurado-Fasoli, L., Dote-Montero, M., Merchan-Ramirez, E., Amaro-Gahete, F.J., Labayen, I., Ruiz, J.R., Sanchez-Delgado, G.
• Format: Article
• Language: English
• Subjects: Between-days reproducibility; Coefficient of variation; Indirect calorimetry; REE; Reliability; Resting energy expenditure
• ISSN: 0939-4753; 1590-3729
• DOI: 10.1016/j.numecd.2023.07.017

Accomplishing a high day-to-day reproducibility is important to detect changes in resting metabolic rate (RMR) and respiratory exchange ratio (RER) that may be produced after an intervention or for monitoring patients' metabolism over time. We aimed to analyze: (i) the influence of different methods for selecting indirect calorimetry data on RMR and RER assessments; and, (ii) whether these methods influence RMR and RER day-to-day reproducibility. Twenty-eight young adults accomplished 4 consecutive RMR assessments (30-min each), using the Q-NRG (Cosmed, Rome, Italy), the Vyntus CPX (Jaeger-CareFusion, Höchberg, Germany), the Omnical (Maastricht Instruments, Maastricht, The Netherlands), and the Ultima CardiO2 (Medgraphics Corporation, St. Paul, Minnesota, USA) carts, on 2 consecutive mornings. Three types of methods were used: (i) short (periods of 5 consecutive minutes; 6–10, 11–15, 16–20, 21–25, and 26–30 min) and long time intervals (TI) methods (6–25 and 6–30 min); (ii) steady state (SSt methods); and, (iii) methods filtering the data by thresholding from the mean RMR (filtering methods). RMR and RER were similar when using different methods (except RMR for the Vyntus and RER for the Q-NRG). Conversely, using different methods impacted RMR (all P ≤ 0.037) and/or RER (P ≤ 0.009) day-to-day reproducibility in all carts. The 6–25 min and the 6–30 min long TI methods yielded more reproducible measurements for all metabolic carts. The 6–25 min and 6–30 min should be the preferred methods for selecting data, as they result in the highest day-to-day reproducibility of RMR and RER assessments. •A high between-days reproducibility is important to detect changes in RMR and RER.•Selecting all/most gas exchange data resulted in more reproducible RMR and RER.•The 6–25 and 6–30 min methods were better associated with RMR classical predictors.•Our study increase confidence in selecting more representative RMR and RER values.•Our findings were replicated in 4 different metabolic carts.