Comparison of Bioelectrical Impedance and Navy Seal Formula to Measure Body Composition in Medical Students

Objectives There are many different ways to measure body composition and bioelectric impedance is one of the most popular methods to measure body ratios. The navy-seal formula is another simple way of measuring body fat ratio which takes into account simple variables such as gender, weight, height, waist, hip and neck circumference. The objective of our study was to compare the results of body fat composition by these two methods. Materials and methods Height and weight were measured in 85 study participants using a wall-mounted stadiometer and digital scale. Body composition measurements were recorded using a simple measuring tape. Participants were then asked to stand on the electrical impedance machine to determine the body fat and muscle mass. Data were analyzed on IBM's statistical package for the social sciences (SPSS) version 23 (IBM, Armonk, NY). Results The Navy-seal formula had slightly higher values for both muscle mass and body fat ratio in both genders and across all body mass index (BMI) categories. Body fat ratio and muscle mass of both genders were similar in underweight, normal, over weight and obese participants. In males, the results on two instruments showed more similarity with the increase in BMI, whereas, in females, the results of the two methods were more similar in the normal weight category. Conclusion Navy-seal formula and bioelectrical impedance are both simple and reliable instruments to measure body composition in adults. The navy-seal formula can be used to screen individuals with high-fat body fat ratio whereas bioelectric impedance can be used to measure the body composition for personal monitoring.