Validation of the ParvoMedics TrueOne® 2400 Metabolic Measurement System for measuring resting metabolic rate in a heterogeneous adult population

Author

Tracie M. Weinheimer, University of Tennessee, Knoxville

Date of Award

5-2006

Degree Type

Thesis

Degree Name

Master of Science

Major

Exercise Science

Major Professor

Edward T. Howley

Committee Members

David R. Bassett, Jr., Eugene Fitzhugh

Abstract

The primary purpose of this study was to validate and compare the accuracy of the ParvoMedics TrueOne® 2400 Metabolic Measurement System in measuring resting VO₂ against the criterion Douglas bag method, and secondarily to compare the Douglas bag measures of VO₂ to those from the ParvoMedics TrueMax® 2400 Metabolic Measurement System, which has been previously validated up to near maximal metabolic rates (3). Resting metabolic rate (RMR) is determined by measuring the oxygen consumption (VO₂) of the subject lying in the supine position in the early morning following an overnight fast. The TrueOne® system uses a “flow-through” methodology, with the subject under a plexiglass canopy; the TrueMax® system measures gas exchange in a conventional manner. Seven males and thirteen females underwent a 30-minute RMR test on each machine; test order was randomly assigned. In addition, expired air was collected into either a Douglas bag or a non-diffusing gas collection bag from the back of the mixing chamber of each system. This allowed a simultaneous measurement of the resting VO₂ to compare the systems to the criterion method. Expired gas volume was determined using a Collins 120 liter gasometer, and O₂ and CO₂ fractions were determined using calibrated gas analyzers. The TrueOne® 2400 systematically underestimated VO₂ compared to the external Douglas bag method by approximately 22% (0.18 L/min and 0.24 L/min, respectively). The TrueMax® 2400 yielded VO₂ values nearly identical to the criterion Douglas bag method (VO₂ = 0.24 L/min and 0.23 L/min, respectively). The systematic underestimation of resting VO₂ by the ParvoMedics TrueOne® 2400 Metabolic Measurement System indicates it is not an accurate device for measuring resting VO₂. The ParvoMedics TrueMax® 2400 is capable of accurately measuring resting VO₂.

Recommended Citation

Weinheimer, Tracie M., "Validation of the ParvoMedics TrueOne® 2400 Metabolic Measurement System for measuring resting metabolic rate in a heterogeneous adult population. " Master's Thesis, University of Tennessee, 2006.
https://trace.tennessee.edu/utk_gradthes/4512