How to Find My Lean Muscle Body Mass

Although many people rely exclusively on the scale to provide validation for their diet and exercise practices, a more telling measure of whether you're improving your overall level of fitness is found by testing body fat levels. Testing your level of body fat draws an important distinction between fat mass and lean mass, allowing you to know exactly whether those 10 or 20 pounds you just lost came from unwanted adipose tissue or precious lean mass.

Instructions

• 1

  Consider caliper testing to provide a reasonable estimate for your total level of body fat. Caliper testing consists of taking skinfold measurements from a number of sites around the body and plugging those numbers into an equation to calculate a best-guess for your current level of body fat. Keep in mind that caliper testing must be performed by a trained expert--individuals who can perform this task are usually available at gyms, rec centers and colleges. Also, note that the more sites used for measurement, the more accurate the reading. So, if you have the choice, favor a nine-site (or more) test over one that only measures skinfolds at three sites.

• 2

  Consider hydrostatic weighing for a more accurate (and more expensive) method of testing your body fat levels. During hydrostatic weighing, you're dunked in a tank of water after expelling all of the air from your lungs, at which point a weight measurement is taken. Body fat is calculated by determining your overall density, as mass from fat floats, because it weighs less than water (whereas muscle sinks as it weighs more than fat). Hydrostatic testing is likely not available at your local gym or rec center, but a nearby college might offer the service for a reasonable fee.

• 3

  Consider DEXA scanning for the most accurate and expensive method of testing body fat. DEXA stands for dual-energy X-ray absorptiometry--body fat is measured by bombarding the body with x-rays to test the amount of mass in your body from high-density bone mass and adipose (fat) tissue. Unlike caliper testing and hydrostatic weighing, which are fairly swift procedures, DEXA can take up to 20 minutes to provide an accurate reading. The test itself can cost upward of $100, so consider the less expensive forms of body fat testing unless you absolutely must know what your body fat is to an extremely accurate degree. If you're interested, your physician will likely be able to set up an appointment for DEXA testing at a local facility.