Bioelectric impedance. A non-invasive technique for measuring body composition.

Bioelectric impedance analysis is a method for determining the lean body mass. One type of BIA involves standing on a special scale with footpads while a small amount of electrical current is sent through the body to calculate the percentage of body fat. Another type of BIA involves electrodes placed on a wrist, an ankle, the back of the right hand and the top of the foot. The change in voltage between electrodes is then measured and body fat percentage is calculated.