Body Fat & Fitness Levels

Body fat is one recognized way to check your fitness levels: dress size is another. But dress size varies vastly by individual and also by the clothing designer, and it really can’t tell you anything about how healthy you are.

On the other hand, body fat measurements can give you an excellent idea of not only how good you look, but of things like how fit your cardiovascular system probably is, how much weight you could lose to maximize your health (and no, “as much as possible” is not the right answer), and whether you might just be in better shape than you thought.

Body fat is usually measured in one of three ways: you may use body fat calipers to determine your ratio of fat-to-muscle, or you may visit a professional and have yourself weighed in water

Called hydrostatic weighing, this method is acknowledged to be the most accurate. You are submerged in a tank of water, and the amount of water you displace is measured. By applying a special formula, the hydrostatic technician can calculate how much of that displacement is due to body fat.

You can also buy a scale or monitor that estimates your body fat using Bioeletrical Impedance Analysis (BIA). The footpad of the monitor sends a slight electrical signal through your body, measuring the resistance of your body to the signal. Because muscles contain more water, they conduct the signal better than fat, which has higher resistance. To arrive at a body fat percentage, the scale uses a formula based on factors such as your height, age, weight and body type, which you input to the computer. BIA monitors are considered very safe and reliable, but they should not be used by people with pacemakers or other medical implants.