How can I measure my metabolism?
This is a common question asked when starting to learn about personal nutrition. RMR, or resting metabolic rate is usually a good place to start.
What is resting metabolic rate?
Metabolism is simply converting food to energy. Metabolic rate is measuring how much food is converted to energy in one day. RMR on the other hand is measuring how much food, or in this case, energy is needed to maintain basic bodily functions like breathing or heartbeats, while at a resting state. Energy is measured in calories, so an RMR will show how many calories are used while resting.
How does this work?
Measuring metabolic rate relies on indirect calorimetry, which relies on the direct relationship that 1 calorie needs about 208 mL of oxygen. The RMR tool used at RBA is the KORR REEVUE indirect calorimeter, which measures the volume of air exhaled and oxygen present. After account for environmental factor like temperature and humidity, the instrument analyzes the results.
How does the resting metabolic rate test work?
It is best to avoid eating 4 hours and to avoid exercise for 24 hours prior to testing. You should also not take any stimulants such as caffeine, but drinking water is fine. During the test you should remain in a still, comfortable position. After the automatic calibration, you will place your mouth on a mouthpiece and keep your lips sealed, taking full breaths out in order for the REEVUE to take an accurate measurement. A gentle clip will be placed over your nose to ensure you are breathing out of your mouth. Breaths should be taken at a normal pace, for ten minutes. Results will be printed out after.
Why should I do this?
RMR is a great base line to start understanding your personal nutritional needs. It give you an understanding of not just energy, but a breakdown of macronutrients. Many clients are surprised by their RMR readings, realizing that they might be eating too few calories than their bodies really need. RMR readings are also more accurate than using calculations alone.
It still important to remember that nutrition is not just about numbers, but we can use tool like RMR testing to supplement an overall approach to nutrition.
Click here to make an appointment for your RMR today!
Rebecca Bitzer loves to empower Registered Dietitian Nutritionists (RDNs) and their clients. Co-author of Welcome to the Rebelution: Seven steps to the nutrition counseling practice of your dreams and Taste the Sweet Rebellion: Rebel against dieting.