Date of Graduation


Document Type


Degree Name

Doctor of Philosophy in Kinesiology (PhD)

Degree Level



Health, Human Performance and Recreation


Michelle Gray

Committee Member

Ro Di Brezzo

Second Committee Member

Nicholas Greene

Third Committee Member

Jamie Baum

Fourth Committee Member

Wen-Juo Lo


aging, appendicular skeletal muscle mass, blood biomarkers, IGF-1, myostatin, sarcopenia


The population comprising older adults is growing exponentially, as are healthcare related costs. Nearly $20 billion is annually expensed by older adults for health-related issues affiliated with age-related decline in skeletal muscle mass. Yet, diagnostic criteria are not readily utilized in clinical practice. PURPOSE: Therefore, the purpose of this study was to provide evidence for use of blood biomarkers (myostatin, IGF-1) to predict appendicular skeletal muscle mass (ASM) among middle-aged and older adults. METHODS: A cross-sectional study was conducted among 106 individuals (n = 68 females; n = 38 males) aged ≥ 40 years of age (60.1 ± 11.1 y) wherein blood biomarkers (serum myostatin and IGF-1) were examined relative to age and appendicular skeletal muscle mass (ASM). Linear multiple regression analysis was used to identify the model of best-fit to describe the relationship between the primary outcome variable (ASM) and the set of biomarkers (myostatin, IGF-1). RESULTS: The results of the regression model indicated 78% of the variance in ASM to be accounted for when utilizing the four-predictor regression model, considering age, sex, serum myostatin and IGF-1. Neither biomarker significantly contributed to the model and only accounted for