How often do we hear about the obesity epidemic in the news?
’ve even heard about it from me. And you may be asking yourself
how we gauge the amount of fat in our bodies, and how much is
How often do we hear about the obesity epidemic in the news? Admittedly, you’ve even heard about it from me. And you may be asking yourself how we gauge the amount of fat in our bodies, and how much is healthy.
First, let me break the body down. Your body is divided into two parts: lean body mass and fat. Lean body mass consists of your muscles, bones, organs, skin (which is actually your bodies largest organ), and water. It’s everything in your body that is not fat.
Fat is just that; it’s just the fat cells. You have a certain number of fat cells. That number doesn’t change. What changes is the size of the fat cells. As you gain weight, they get bigger. As you lose weight, they get smaller.
Before I continue, I’d like to clear up a common misconception: muscle and fat are two different things. One does not turn into the other. I have heard people say things like “I haven’t exercised in so long. All my muscle has turned into fat.” This statement is untrue. Muscles, when not used, may get smaller and weaker. Fat cells may grow. But one does not turn into the other.
There are several ways to measure body composition. Some are more accurate than others. However, the more detailed ones are usually available only in clinical settings such as hospitals and tend to be expensive. The “gold standard” of body fat measurement is hydrostatic (underwater) weighing. This is where you compare your weight on land to your weight in a pool. Since fat floats, and muscle doesn’t, this is a great indicator. You expel as much air as you can out of your lungs and are dunked underwater. The more you float the more fat you have in your body.
Bioelectrical impedance is another readily, and less expensive, means of measuring body fat. It is available on many home scales and via hand-held instruments. This method sends a small, painless electrical signal through your skin. Because of its chemical properties, muscle has no electrical conductivity, but fat does. This instrument measures the total amount of electrical resistance. However, the level of hydration in your body may affect the results since water is extremely conductive.
Another way that is often used to determine healthy body weight is using a body mass index (BMI) scale. BMI uses a simple formula that compares height and weight. However, BMI does not distinguish between fat mass and lean body mass. I have seen “skinny” people who are technically obese, and large people who are actually quite lean.
It is also important to know that the location of fat on your body plays a role in the health risks it poses. The fat right under your skin (known as subcutaneous fat) does not increase your likelihood of having heart disease, diabetes, or other serious diseases. However, fat that surrounds your organs deep within your abdomen (visceral fat) is a major indicator of these risks. For this reason, many doctors will rely a waist to hip ratio measurement as a way of gauging body fat. The larger your waist is in comparison to your hips, the more fat you have in your abdomen, and the higher risk you have for developing these diseases.
Xtreme Fitness in Morgan Hill has body fat testing (skinfold calipers and bioelectrical impedance) available. Mention this article and receive 30 days for $30.00 or 14 days free.
Karen Frost is the Personal Training Director for Mavericks Sports Club in Morgan Hill. She holds a Master of Arts degree in Physical Education/Fitness Management from New York University, and is certified by the American Council on Exercise as a Personal Trainer and a Lifestyle and Weight Management Consultant.