Body Composition Assessment

Part of anthropometric assessment is the determination of body composition. The measurements provide information on muscle mass (lean weight) and fat reserves. 

There are different methods of measuring body composition:

1) Calipers


3) Hydrostatic weighing

4) Bioelectrical Impedance


Pros: It is portable and most gyms offer for little or no cost. It is quick.

Cons: Some people may find it uncomfortable and invasive. The accuracy of the skinfold is dependant on the technician’s skill as well as the calliper type and the skin fold prediction equation used. Results vary when done by different technician.

DEXA (Dual Energy X-ray Absorptiometry) 

Pros: This method is considered a gold standard because of its reliability, precision, and the fact that it is based on three body components (fat, muscle, bone) rather than two (fat and muscle) as in most other methods including hydrostatic weighing. It allows fat distribution throughout the entire body to be read in a single scan. 

Cons: Expensive and a person must lie perfectly still for 10-20 minutes while the scan is taken. You are exposed to radiation. DEXA is found mainly in research facilities and through some X-Ray services. 

Hydrostatic Weighing 

Pros: Done correctly, this method is also quite accurate and considered a gold standard. 

Cons: Hmm, uncomfortable to say the least! The test relies upon the person’s ability to expel all oxygen from their lungs while submerged in a tank of water. Oxygen remaining in the lungs will skew the results. In clinical settings, this procedure is repeated a number of times, and an average is taken. The “tank” is expensive and the inconvenience to the user is considerable. Because of the cost, lengthy testing process, and physical burden to the subject, this method is more suitable for research studies. 

Bioelectrical Impedance

Bioelectrical impedance analysis uses a very small electrical signal to measure body impedance. The signal is conducted through the water contained in the body. Lean muscle has much more water than fat tissue and allows the signal to pass easily. It is measuring the resistance electricity varies between fat, muscular and skeletal tissue.Fat causes impedance or resistance to the signal. This is the method we use for body compostion assessment.

Pros: Affordable and relatively simple and quick assessment. The device we use produces very accurate results that are highly correlated with both DEXA and hydrostatic weighing. Measurements are very repeatable when tests are performed under consistent conditions. 

Cons: Some machine does not take into account of gender, therefore it is less accurate. The one we use does. This is important because men and women store fat differently around the abdomen and thigh region, the results can be less accurate as a measure of total body fat percentage.

Results are effected by hydration, such as alcohol or food consumption or alcohol, sleep, intense exercise, medication or pre-menstruation or simply having a very full bladder during the assessment.  

Test can be skewed if taken at different times of the day. For a more accurate result, test at the same time of day, preferably before meals, before training, and after hydrating.

How to get the greatest accuracy out of our monitor:

If your body is dehydrated, you will likely experience a higher than normal reading. If you are over-hydrated, you could experience a slightly lower reading. We suggest the following protocol:

  • Take readings at least 3 hours after rising, eating a large meal, or exercising.
  • Taking readings more than once per week is not beneficial since body fat does not change from day to day.)
  • Average your readings for the month (if you’re monitoring weekly)
  • Compare average

Take readings once a week or month at the same time of day under the same conditions from month to month.By following this format, hydration fluctuations throughout the month will average out, and you will be able to better assess any real change in your body fat percentage over time.


Is it safe to use the monitor if I’m pregnant? 

There is not enough research done on this population, so we do not recommend the use. Since there are dynamic physiological changes that occur during pregnancy, a pregnant woman cannot expect an accurate body fat reading.

I have an electronic medical device or implant, is it safe for me to use the monitor? 

You should not use the monitor if you have a pacemaker or other electronic medical implants . Non-electronic medical implants are fine and you may safely use the monitor. Any metallic implant in your body could affect the body fat reading, giving a slightly lower than normal reading. However, since the metal will continue to have the same affect on the reading each time you use the monitor; you can still use the monitor to successfully track the relative change in body fat over time.

Is this suitable for Body Builders or professional athletes? 

If you are an adult who has approximately 10 hours of intense physical activity per week and have a resting heart rate of approximately 60 beats per minute or less, you probably considered a professional athlete. 

You may obtain a higher than normal body fat reading. Despite this fact, you may still want to use our monitor to gauge their progress of losing body fat. The great repeatability of the product enables one to establish a baseline and use the product for “trending purposes” to assess loss or gain in body fat over time.

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