Resting energy expenditure (REE) testing
Resting Energy Expenditure (REE) testing represents the exact number of calories your body burns at complete rest to maintain vital functions such as heart activity, breathing, body temperature regulation, and brain function. In an average person, REE accounts for as much as 60% to 75% of total daily energy expenditure. This means that most calories are not burned during activity, but while you are sitting or sleeping.
Who is REE testing for and what does it reveal?
This test is intended for individuals who want to lose weight and avoid the “yo-yo” effect (REE testing helps determine a safe caloric deficit), as well as for people with metabolic disorders, supporting the treatment of insulin resistance or thyroid-related issues. It is also used by athletes to optimize energy intake and improve performance without losing muscle mass.
Precise REE measurement reveals:
- Whether your metabolism is slowed down – often seen in individuals who have followed restrictive diets.
- Exactly how much you should eat – providing a precise calorie number below which you should not go if you want to lose weight in a healthy way.
- The effectiveness of your diet – allowing us to tailor a nutrition plan based on your actual energy expenditure rather than assumptions.
What does REE testing look like?
During the test, you lie or sit still for 15 to 20 minutes while wearing a mask and the device measures the exact ratio of oxygen consumed (VO2) and carbon dioxide exhaled (VCO2). This gas exchange directly shows how much “fuel” your cells are currently burning.
The respiratory quotient (RQ) reveals whether your body primarily uses fats or carbohydrates at rest. If your body burns only sugars at rest, it is a sign of metabolic inflexibility, which can be improved through targeted exercise and nutrition.
