Measuring Body Fat
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Measuring Body Fat
Ideal competition weight is different for each individual just as body fat percentage is different. Ensure you are working with a professional if you are looking to improve your body composition.
Body fat can be measured in several ways, and some methods are more reliable than others are.
Body Mass Index (BMI) is a measure of body fat based on weight and
height. BMI is used by doctors as a general indicator of health, but BMI does not take into
account whether the weight is carried as fat or muscle. Therefore, BMI
can be highly inaccurate for athletes. Athletes with a
high muscle mass may have a high BMI but they are unlikely to be at a greater health
risk.
The skin fold method measures body fat by using the hand to pinch the fat and then measuring the thickness with a body fat caliper. The reading is given in millimetres, which you compare to a chart with gender and age to arrive at a body fat percentage. The skin fold method is the least accurate and least dependable method for measuring body fat percentage.
Dual-energy X-ray Absorptiometry (DEXA or DXA) is highly accurate and is based on a system that divides the body into total body mineral mass (bone density), fat-free soft (lean) mass, and fat tissue mass. DEXA allows for analysis of body fat distribution or how fat is distributed in various parts of the body. The procedure is completely safe, using a body scanner with low dose x-rays, and takes about 10 to 20 minutes. However, this method can be expensive, ranging from $85 to $250.
Hydrostatic weighing is considered one of the most reliable body fat measurements and requires being submerged in a tank of water. Muscle and bone (lean tissue) are more dense than water is, and fat tissue is less dense that water is. Therefore, a person with a large percentage of fat-free matter weighs more in the water and has a lower percentage body fat. A large amount of fat mass makes the body lighter in water, which means the person has a high percent body fat.
The test costs about $100 to $150 and takes about 20 to 30 minutes; it is available at universities, hospitals, or research labs.
The test costs about $100 to $150 and takes about 20 to 30 minutes; it is available at universities, hospitals, or research labs.
Bioelectric Impedance Analysis (BIA) determines the electrical impedance (opposition to the flow of an electric current through the body). Muscle has high water content and is highly conductive, but fat has lower water content and is not highly conductive. The BIA scale estimates fat-free body mass and body fat percentage based on the strength of the impedance along with height and weight measurements. However, because the BIA test is based on body water balance, the state of hydration can affect the level of accuracy.
