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Bioelectrical Impedance Analysis

a bio-electrical machine
Bioelectrical Impedance Analysis (BIA) is a commonly used method for estimating body composition, in particular body fat and muscle mass. In BIA, a weak electric current flows through the body and the voltage is measured in order to calculate impedance (resistance) of the body.

Bioelectrical Impedance Analysis:

  • Uses a small electric current to differentiate between fat (low water content) & other body tissue (higher water content)
  • Gives an estimate of total body water
  • Very user-friendly and can give good results for comparative purposes.

Issues to be aware of with BIA:

  • Test protocols need to be strictly adhered to for good comparative results
  • The test can be affected by body position, hydration, food and beverage consumption, air and skin temperature and recent physical activity
  • Sensitive to the density of components of the body
  • Arm and leg electrodes will give more accurate results than the arm to arm electrodes.

To explore BIA further, we advise you to access this course reading – Bioelectrical impedance analysis to estimate body composition in children and adolescents

© CQUniversity 2021
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