Validity of using multi-frequency bioelectrical impedance analysis to measure skeletal muscle mass in preschool children

[Purposes] Although it is recommended to develop a habit of physical activities, there is no easy way to measure skeletal muscle mass in preschool children, which cause the difficulty of evaluation. The purpose of this study was to examine the validity of body composition including the skeletal muscle mass assessment using multi-frequency bioelectrical impedance analysis by comparing body fat mass obtained by using multi-frequency bioelectrical impedance analysis method and body mass index formulas. [Subjects and Methods] Ninety-four children were surveyed for age, height, weight, grip strength, maximum occlusal force, thickness of muscle and fat mass (masseter and lower limb), body fat mass, skeletal muscle mass, and calf circumference. We assessed additional parameters, which were thought to be related to skeletal muscle mass, to ensure validity. [Results] A strong correlation was found in body fat mass values obtained using the multi-frequency bioelectrical impedance analysis method and those obtained using the body mass index formulas. Additionally, strong correlation coefficients were found between the skeletal muscle mass/height obtained using the multi-frequency bioelectrical impedance analysis method and grip strength and calf circumference. [Conclusion] Our results indicate that skeletal muscle mass can be reliably measured using the multi-frequency bioelectrical impedance analysis method in preschool children.