Contents
In this article you will learn, among others:
- What are the methods of measuring body composition?
- What is the DXA method?
- How does scale work with body composition analysis?
- Is the weight measurement with body composition analysis reliable?
- How to properly measure body composition?
- What are the body composition standards?
What are the methods of measuring body composition?
It should be remembered that the body composition test is only an estimate. It is impossible to determine with 3% accuracy the content of individual components in the body. There are several methods of measurement, some of them are less accurate. They are divided into XNUMX groups:
- reliable methods – Dual energy X-ray absorptiometry (DXA), hydrostatic method,
- less reliable methods – bioelectric impedance (BIA), infrared impact assessment (NIR),
- the least reliable methods – skin folds assessment, body circumference measurements.
What is the DXA method?
DXA is considered the most accurate method. In its case, the flow of the ionizing radiation beam is analyzed and its weakening is checked. It is used in professional equipment, especially to test the body composition of athletes. Its big advantage is showing the exact location of individual components in the body, e.g. that the most fat is on the belly. It also allows you to determine the density of the skeleton. Hydrostatic methodwhich is also quite accurate is otherwise known as underwater weighing and is based on Archimedes’ law.
How does scale work with body composition analysis?
In the case of home appliances, it is mainly used the BIA method, that is, a weak beam of current flowing through the body of a small intensity and a certain frequency (most often around 50 kHz). Then the tissue resistance (impedance) to the transmitted current is examined. Water, muscle or blood passes electricity, and fatty tissue resists. This allows you to determine the fat content and lean body mass. Thanks to this, it is possible to determine the ratio of fat to muscle. The method is safe, non-invasive and imperceptible, or you may feel a slight tingling sensation. However, contraindications to use are pregnancy, epilepsy or implanted cardiac defibrillator. Ideal?
Is the weight measurement with body composition analysis reliable?
Producers tout their articles as being super accurate, but the truth is that when it comes to BIA it is very important how to carry out the measurement. The result is influenced by many factors, which the producers often forget to mention, and the measurement itself is burdened with an error. Additionally, most home appliances have only electrodes on the feet and the measurement is made in a standing position. The current goes the shortest way. This means that when measuring in this way, the beam flows from one leg to the other, so the analysis covers only half of the body. Research indicates a reduction in accuracy in this type of measurement. A significant improvement in the results is achieved in the connection of the foot-hand electrodes. It is also important horizontal position, to equalize body fluid levels, but also to increase impedance. Unfortunately, this is not possible with home appliances. It is also worth noting that in the case of obesity high fat content changes impedance, which also distorts the result and may require the introduction of a higher current frequency during the measurement. Weighing the frequency of the current at home, we will not change it.
How to properly measure body composition?
The analysis of body composition at home should therefore be taken with a pinch of salt and on the basis of control of the order of changes rather than precise calculations. In order for the measurements to be actually related, several conditions must be met:
- measurement must be made always at the same time of the day, preferably in the morning on an empty stomach (at least 4 hours after a meal) 30 minutes after emptying the bladder,
- 12-24 hours before the test should be avoid coffee, strong black tea, energy drinks, alcohol,
- do not drink anything before the testbecause it disturbs the reading (an additional liter of water drunk will indicate additional muscle content, which will be a distortion),
- do not measure after exercise and sauna (preferably 12 hours apart) as getting rid of the water through sweat (dehydration) will show more fat than it really is,
- the reading is also influenced by the use diuretics (dehydrating drugs), swelling and in the case of ladies menstrual cycle (best to measure in the middle of the cycle).
What are the body composition standards?
The content of individual components in the body and their relation to each other allows us to determine, for example, whether obesity appears in us with a normal body weight, or vice versa, despite a high body weight, we have a high content of muscles and low fat. What are the standards?
- Water content – women 55-62 percent (the older the person, the lower the norm), men 58-65 percent.
- body fat content – women 16-20% (28-30% norm for women> 70 years old), men 15-22%.
- lean body mass (bones, muscles, internal organs, body fluids) – women 70-80% (the norm decreases with age), men 75-85 percent.
So is it worth buying a scale with a body composition analyzer? Only then when we remember about the ‘flaws’ of such a measurement and we will only consider it as a way to analyze differences in measurements. Then, such an analysis will help us to observe the changes that occur in the body as a result of the diet. However, you should remember about proper preparation for the measurement and always taking it at the same time of the day.
Have you ever used body composition measurements on a scale? What is your opinion on weight measurement?
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