How exactly is my body fat and water measured?
Salter scales use a measurement method known as Bioelectrical Impedance Analysis (BIA). A minute current is sent through your body, via your feet and legs. This current flows easily through the lean muscular tissue, which has a high fluid content, but not easily through fat. Therefore, by measuring your body’s impedance (i.e. its resistance to the current), the quantity of muscle can be determined. From this, the quantity of fat and water can then be estimated.
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