Bioimpedanssimittaus

Bioimpedanssimittaus, also known as bioelectrical impedance analysis (BIA), is a method used to estimate body composition. It involves passing a low-level electrical current through the body and measuring the resistance or impedance to that current. Different tissues in the body have varying electrical properties. Fat tissue, for example, contains less water and electrolytes than muscle or bone tissue, and therefore has higher impedance.

The electrical current used in BIA is imperceptible to the individual and is considered safe. Electrodes are typically placed on the hand and foot, or on both hands and feet, to allow the current to flow through the body. The device measures the voltage drop and calculates the impedance. This impedance value is then used in conjunction with other data, such as height, weight, age, and sex, in predictive equations to estimate body fat percentage, lean body mass, total body water, and sometimes even basal metabolic rate.

BIA is a non-invasive, relatively inexpensive, and quick method for assessing body composition. It is widely used in clinical settings, fitness centers, and research. However, the accuracy of BIA can be influenced by various factors, including hydration status, recent food intake, physical activity level, and the specific BIA device and equations used. Therefore, it is important to follow standardized protocols for measurement and to interpret the results with an understanding of these potential limitations. Despite these factors, BIA can be a useful tool for tracking changes in body composition over time.