Metabolism is the rate at which your body uses energy, or, burns calories. Your resting metabolism measures the number of calories required to keep your body functioning.
Your metabolism burns calories all the time, whether you're just sitting on the couch or you're jogging around the block.
Even while we sleep our metabolism is working. Your body is using up energy to keep running -- to make your heart beat, your kidneys function, and so on.
Your Basal Metabolic Rate (BMR) is the number of calories you would burn even if you slept all day and night.
Many factors can affect your BMR, including your age, health, stress level, and even the temperature of your environment.
To get a general idea of what your BMR is, multiply your weight by 10. If you weight 150 pounds then your BMR = 150 x 10 kcal/lb = 1,500 kcals (kcals stands for the number calorie burned).
Your true resting metabolic rate will vary from any one else around you. It is influenced mainly by your body size and muscle mass, as well as genetics.
To get a more accurate estimate of your metabolism, a qualified trainer or a registered dietitian can measure it on a small device like a calculator. It will compute the number of calorie you actually burn per minute -- an estimate of your resting metabolism.
Inquire at your local fitness center or hospital to see if they offer this service.