Resting metabolic rate
Resting Metabolic Rate (RMR) is a form of metabolism measurement that measures the amount of energy used by the bodies of animals in a relaxed, but not post-absorptive, state. RMR measurements require the animals be in a thermal neutral zone (or a preferred temperature range for bradymetabolic animals) and relaxed. Animals are given the freedom to move around and eat, but are not allowed to perform any strenuous exercises. This differs from basal metabolic rate measurements in that it does not require that animals meet the strict criteria necessary for a proper BMR measurement. The less strict criteria of RMR measurements makes them more applicable for many biological studies.
- , where LBM is the lean body mass in kg
Since lean body mass is metabolically active vs. fat cells which need very few calories to be sustained, these formula tend to be more accurate, especially with athletes who have above average lean mass and little body fat.
To calculate daily calorie needs, the RMR value is multiplied by a factor with a value between 1.2 and 1.9, depending on the person's physical activity level.
Indirect calorimetry remains the gold-standard method to measure RMR. Although traditional indirect calorimeters are designed for the laboratory and clinical setting, technological advancements in biosensor research have allowed RMR to be measured in free-living conditions. The first mobile metabolic tracker (Breezing® Metabolism Tracker) was developed by researchers and engineers from Arizona State University in 2012.
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- Buch, Karen (January 6, 2016). "Breezing® Mobile Indirect Calorimeter". Nutrition 411. Retrieved Jan 21, 2016.
- "Personalized Indirect Calorimeter for Energy Expenditure (EE) Measurement". www.peertechz.com. Retrieved 2016-01-22.
- "Measuring Your Metabolism: Breezing at QS15 - Quantified Self". Quantified Self. Retrieved 2016-01-22.