The present study examined characteristics of the body composition of elementary and junior high school students (1,323 boys, 455 girls) who were between 6 and 15 years old. The participants’ body fat mass (BFM) and lean body mass (LBM) were measured by the electrical impedance method; the thickness of their muscle and subcutaneous fat was measured by B mode ultrasonography. The partial correlation coefficients between LBM and a muscle mass index (MMI: muscle thickness(cm) x body height(m)) were statistically significant (boys, 0.782; girls, 0.766), as were the correlation coefficients between BFM and subcutaneous fat mass index (SFMI: fat thickness(cm) x body height(m)), (boys, 0.936; girls, 0.914). The MMI increased with body height, most notably in the boys over 151.7 cm and the girls over 144.7 cm in height.
View full abstract