Prediction Of Skeletal Muscle Mass From 541 Women And Men Aged 6 To 87 Years

PURPOSE: This study aimed to develop a prediction equation for skeletal muscle mass (SMM) using measurable indicators in the field of exercise instruction for a wide age range. METHODS: The participants included 259 women and 282 men aged 6-87 years. Skeletal muscle mass was assessed using a wearable body composition analyzer, and handgrip strength and vertical jump height were measured. The participants were randomly separated into either a validation group (130 women and 141 men) or a cross-validation group (129 women and 141 men), and a hierarchical multiple regression analysis was conducted on the validation group to derive an estimation formula for SMM. RESULTS: The regression equation for estimating SMM using age, sex, height, body weight, handgrip strength, and vertical jump height as independent variables [SMM (kg) = −0.002 × age + 1.702 × sex (women = 0, men = 1) + 0.13 × height (cm) + 0.244 × weight (kg) + 0.078 × handgrip strength (kg) + 0.096 × vertical jump height (cm) −16.711] was validated (adjusted R2 = 0.96) and cross-validated (adjusted R2 = 0.96). No significant difference was found between the measured and estimated SMM values in either group. The Bland-Altman analysis indicated no systematic errors in either group. CONCLUSION: The prediction equation for SMM using measurable indicators in the field of exercise instruction was shown to be applicable to women and men with a wide age range. Supported by: Japan Society for the Promotion of Science KAKENHI grant JP24K14515