This study aims to characterize SMI in BMI of young women.
The participants were 80 young adult females (mean age 21.2±0.7 years). InBody 270 (In-Body, Inc.) was used. The height, weight, and skeletal muscle mass (SMM) of the limbs were measured. BMI was calculated using height and weight, and SMI was calculated using height and SMM. We excluded participants with metal implants (e.g., pacemakers and implants), those who had eaten within four hours, those who had defecated or urinated before defecation, and those who had exercised after exercise, as these factors were considered to affect the values. The participants were measured barefoot and with 1.0 kg of clothing subtracted from their total weight. They were divided into three groups: underweight, normal weight, and obese. The Kruskal-Wallis test was used for statistical analysis, and the Bonferroni method was used for multiple comparison tests. The significance level was set at 5%. This study was approved by the Ethics Committee of the International University of Health and Welfare (18-Io-17).
The participants had a height of 159.2±4.7 cm, weight of 51.2±5.8 kg, SMM of 20.4±2.1 kg, BMI of 20.2±2.1 kg/m2, and SMI of 7.9±1.0 kg/m2. Among the participants, 16 (20％) were underweight (18.5 kg/m2 ), 62 (77.5%) had normal weight (18.5 kg/m2≤ – 25 kg/m2 ), and two(2.5%) were obese I (25 .0 kg/m2≤ – 30 kg/m2 ). One participant (1.3%) had a low BMI and SMI, and two participants (2.5%) had a normal BMI and low SMI. The results of multiple comparison tests showed significant differences between the low and normal BMI and obese I BMI groups (p0.05).
Not only can low BMI and weight be associated with low SMI, but low SMI can also be associated with normal BMI. Therefore, even if a person does not have a BMI problem, this does not guarantee the avoidance of the risk of sarcopenia due to a low SMI.
In addition to BMI, body composition can also be measured to detect the risk of muscle loss at an early stage.
Body Mass Index
Skeletal Muscle Index
