Phase Angle Measurement in Healthy Human Subjects through Bio-Impedance Analysis

Document Type: Original Article


1 Department of Physiology, Yenepoya Medical College, Deralakatte, Mangalore-575018. Karnataka, India

2 Department of Radiology, Yenepoya Medical College, Deralakatte, Mangalore-575018. Karnataka, India


Bioelectrical impedance is the measure of impedance of the body. Impedance consists of electric resistance and reactance. Phase angle (PA) is the tan value of the ratio of reactance versus electric resistance. PA depends on cell membrane integrity and on body cell mass. There exists a correlation between PA values and body cell mass.
The objective of this study was to compare the PA values of normal individuals and their anthropometric measurements.
Materials and Methods
Anthropometric measurements, Bioelectrical impedance analysis and PA measurements were done using Bodystat Quadscan 4000 machine on 42 healthy subjects between the age group of 18 to 50 yrs at a private hospital, Bangalore, Karnataka, India for eight months. Kolmogrov-Smirnov and Pearson’s correlation tests were used for data analysis.
The PA values were 7.321.17º in healthy subjects. PA values were significantly positively correlated with body mass index (BMI) (r= 0.011, P<0.001). The phase angle values for males and females were 7.43±0.98º and 7.05±1.1.58º, respectively.
PA values positively correlated with BMI indicating the nutritional status of the study group. PA values were similar to the values to found in other studies.


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