RMRratio provides an indication of energy availability by comparing measured resting metabolic rate (RMR) to that predicted by an equation using values such as age, height, and lean mass. RMRratio has been associated with psychological variables such as cognitive restraint (CR) and Drive for Thinness (DT) in young, active women. PURPOSE: The purpose of this study was to assess the strength of correlation between these psychometric variables and RMRratio values using a variety of RMR prediction equations. METHODS: Forty-one generally healthy women were included in this analysis. All participants self-attested to engaging in two or more hours of moderate- to vigorous-intensity exercise per week, of any modality, for the past three months or more. Participants abstained from all food, fluid, caffeine, and alcohol for at least 8 hours and from exercise for at least 24 hours prior to their visit. Body fat percentage (BFP) was obtained via dual-energy X-ray absorptiometry (DXA; Lunar iDXA, General Electric). RMR was measured using a metabolic cart (TrueOne 2400, Parvo Medics) with ventilated hood. After 30 minutes of supine rest, gas was collected for a minimum of ten minutes with the first five minutes discarded. Data were collected until coefficients of variation <10% for VO2 and VCO2 and <5% for RMR were achieved, with the average of the final five minutes used. CR was assessed using the Three-Factor Eating Questionnaire Revised 18-item form (possible range: 6-24) and DT was assessed using the raw score generated from the Eating Disorder Inventory 91-item questionnaire (possible range: 0-21). RMRratio values were calculated using five equations (Harris-Benedict 1918; Cunningham 1980 and 1991; DeLorenzo 1999; and ten Haaf & Weijs 2014). As CR and DT scores were considered non-parametric data, correlations were analyzed using Spearman's ρ corrected for multiple comparisons. RESULTS: Participants (mean ±SD age: 21.7±3.7 years, height: 164.4±6.1 cm; weight: 64.8±9.3 kg; BFP: 33.2±5.9%) had an average measured RMR of 1624±191 kcal/day, CR score of 12.4±4.0, and DT score of 4.2±5.6. Correlation values with CR ranged from -0.39 (ten Haaf & Weijs) to -0.29 (Cunningham 1991) and were statistically significant (p<0.05) for only the Delorenzo and ten Haaf & Weijs equations (ps≤0.04). Correlation values with DT ranged from -0.27 (ten Haaf & Weijs) to -0.14 (Cunningham 1991) but were not statistically significant for any equation (all ps≥0.31). CONCLUSION: In previous research, RMRratio has been correlated with psychological variables traditionally associated with low energy availability, namely CR and DT. In our sample of young, exercising women, RMRratio using the ten Haaf & Weijs (2014) equation was most strongly correlated with CR and equally unassociated with DT when compared to four other equations. Future research using this equation within RMRratio analyses is warranted.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.