Definition of Total Body Mass
You can assess your overall level of fitness and health in various ways, ranging from blood pressure to cholesterol measurements. But if you've ever heard the term "total body mass," you may wonder how that concept relates to your weight, or your Body Mass Index.
"Total body mass" refers to the total mass of your body, and is usually measured by a standard scale. It includes all of your body's components: fat, muscle, bone, organs, tissues, and so forth.
Total Body Mass and Weight
Even though your total body mass can be measured with a standard scale, it is technically not equivalent to your weight alone, and the two terms should not be confused. Weight simply refers to how much downward force something exerts in a gravitational field, while mass is a more technical term in physics, implying an object's capacity for inertia. Despite this difference, however, for most purposes total body mass can be measured in the same way as weight: with a standard scale.
Total Body Mass and Body Mass Index
Total body mass and Body Mass Index are similar but distinct concepts which measure very different things. Your Total Body Mass is the total mass of all the substances in your body, while your Body Mass Index is your body's ratio of fat to other tissues.