What is body composition?
Not all weight is created equal. Our bodies can be divided into two main components – fat and lean mass. Fat is classified as two types. The first, “essential fat”, is necessary for normal body function. The second type is “storage fat”, which is the extra fuel we store under the skin, in the muscle, and around various organs. Lean mass primarily consists of muscle, the major “metabolic” engine of the body. The more muscle in your body, the more calories you will burn (even when resting).
Although people commonly make reference to being “overweight”, having excess body weight and excess body fat are two completely different things. While it is true that a pound of fat and a pound of muscle each weigh a pound, that’s were the similarity ends. As explained by Daniel Kosich, PhD, “Fat and muscle differ in an important way – muscle is much denser than fat. Think of it this way: Muscle is like a brick. Fat, on the other hand, is like cotton balls.
It takes far more cotton balls than brick to make a pound. So a pound of fat takes up more space on your body than a pound of muscle.” With this in mind, it is important to note that a person beginning an exercise and nutrition program will in many cases gain weight, because they are losing body fat and gaining muscle mass. Therefore, muscular individuals can have a high body weight without actually having excess body fat.
Why is body composition important?
It is one of the best indicators of health! Body composition (percent fat and lean) reflects the results of both physical activity and nutritional practices. Body weight alone can be very misleading. The scale cannot tell the difference between a pound of fat and a pound of muscle. Over time, people tend to gain fat and lose muscle without an obvious change in their weight. And, even though we need a certain amount of fat in our bodies to insure good health, excess body fat has been found to increase the risk of diseases such as cancer, diabetes, and heart disease.
In fact, the Centers for Disease Control and Prevention (CDC) have now declared obesity an epidemic, with 66% of adult Americans either overweight or obese (having excess body fat). On the other hand, too little body fat can also pose a number of health risks, especially for women. Only by accurately measuring body composition will you learn the amount of fat and lean tissue that makes up your weight, enabling sensible decisions regarding nutrition and exercise programs. It is the best way to get the “whole picture” of what is really going on in your body.