Health and Fitness Information Center

The Study of Body Composition

• Health Topics

• Asthma/Allergies
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• Body Fat Measuring
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Adding further to the acceptance of this practice is the importance of body composition in athletic performance and its move from being a laboratory-only procedure to one used in ordinary medical practice and now health clubs or at home. By measuring body composition, a person's health status can be more accurately assessed and the effects of both dietary and physical activity programs better directed.

Most people don't realize that there is only one "direct" method of measuring body composition that is close to 100% accurate, and that is an autopsy - performed Post Mortem . All other current methods for measuring body composition rely on "indirect" measurements techniques and are called In Vivo methods - meaning they are performed on a living body.

In Vivo methods give estimates of percentage of body fat, fat-free mass, muscle, bone density, hydration, or other body components. Each method uses one or more measurable body component (such as skinfold thickness, resistance, etc.) to make educated predictions about the other components. These predictions are based on years of research that define statistical relationships between different body components.

According to the National Institutes of Health, no trial data exist to indicate that one method of measuring body fat is better than any other for following overweight and obese patients during treatment. Good results depend upon accurately taken measurements and an adequate, scientifically derived database. Every measurement method has strengths as well as defined sources of error. Most research studies employ several methods used in combination.

Body composition equipment manufacturers should have scientific studies available to support accuracy claims, but often companies fail to explain the problems encountered in day-to-day use outside of the controlled environment of a research lab. Tanita feels it is very important for people to fully understand the benefits - and limitations - of body composition analysis. This information will enable people to make better decisions about which method is the best or most appropriate for their particular needs.