Resting energy expenditure

Resting energy expenditure, abbreviated as REE, is the amount of energy, usually expressed in kcal (food calories), required for a 24-hour period by the body during resting conditions. It is closely related to, but not identical to, basal metabolic rate.

Resting energy expenditure can be measured using indirect calorimetry. While different collection methods exist, more recent advancements include a mobile indirect calorimeter (Breezing® Metabolism Tracker) that have made REE measurements possible under free-living conditions.

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