Room Indirect Calorimetry Operating and Reporting Standards (RICORS 1.0): A Guide to Conducting and Reporting Human Whole‐Room Calorimeter Studies

Abstract

Whole‐room indirect calorimeters have been used to study human metabolism for more than a century. These studies have contributed substantial knowledge to the assessment of nutritional needs and the regulation of energy expenditure and substrate oxidation in humans. However, comparing results from studies conducted at different sites is challenging because of a lack of consistency in reporting technical performance, study design, and results. In May 2019, an expert panel was convened to consider minimal requirements for conducting and reporting the results of human whole‐room indirect calorimeter studies. We propose Room Indirect Calorimetry Operating and Reporting Standards, version 1.0 (RICORS 1.0) to provide guidance to ensure consistency and facilitate meaningful comparisons of human energy metabolism studies across publications, laboratories, and clinical sites.

Prolonged Glucagon Infusion Does Not Affect Energy Expenditure in Individuals with Overweight/Obesity: A Randomized Trial

“…For all other repeated‐measures variables, differences among the groups were measured via a repeated‐measures ANCOVA, which was followed by post hoc multiple comparisons, with EE and substrate oxidation variables adjusted for fat‐free mass. For EE variables, day −1 was used as the baseline value, as it was more representative of true WRC behavior (15). To determine the effect of change in EI on change in EE between groups, ANCOVA was performed with the change in EI and baseline EE used as covariates.…”

“…A WRC (10 feet by 12 feet by 9 feet, 30,000 L) operated with a push-pull system, maintained at thermoneutrality at 22.5 °C, and maintained at a relative humidity of 50% to 65% was used to assess EE and substrate oxidation (15). VO 2 consumption and VCO 2 production in the chambers were measured using gas analyzers (Ultramat/Oxymat 6; Siemens, Bartlesville, Oklahoma).…”

Reliability of measurements of energy expenditure and substrate oxidation using whole‐room indirect calorimetry

“…The subtleness of differences in EE expected after the intervention will ultimately help to determine the measurement period required to power a study using whole-room calorimeters. (7). Therefore, studies documenting the reliability of whole-room calorimeters are now critical to power such trials.…”

“…Indeed, whole-room calorimeters (often called metabolic chambers) can capture the individual components of 24-hour EE (24hr EE) including (1) RMR, (2) thermic effect of food (TEF), and (3) activity thermogenesis (6,7). The RMR represents approximately 70% of 24hr EE and it is determined by fat-free mass, fat mass, sex, and age, as well as genetic factors (7,8). The TEF is the smallest component of 24hr EE (approximately 10%), and it refers to EE above fasting EE divided by the ingested energy (9)(10)(11).…”

Novel Equations to Estimate Resting Energy Expenditure during Sitting and Sleeping

“…Moreover, dietary-induced thermogenesis almost disappeared within 6 h of the mean [42,43], and we believe there was minimal effect on sitting mREE measurement due to a fasting period of at least 10 h [44]. Third, a few studies described the effect of habituation [45,46]. In this study, there were 65 participants in the first experiment using a metabolic chamber.…”