CAUSAL STRUCTURE BETWEEN MUSCLE, MOTOR AND LIVING FUNCTIONS IN COMMUNITY DWELLING ELDERS / 体力科学

ABSTRACT

The purpose of this study was to confirm the causal structure model of muscle, motor and living functions utilizing structural equation modeling (SEM) . As subjects, 103 community-dwelling older men and women, aged 65.7±6.9years of age, participated in the study to measure muscle cross-sectional area, maximum voluntary contractions, muscle power, 4 physical performance tests, and 16 questionnaires regarding ability of activities of daily living. The causal structure model of muscle, motor and living functions was hypothesized to be a hierarchical causal structure. The causal structure model of muscle function was hypothesized to be a hierarchical causal structure consisting of 3 sub-domains of muscle mass, muscle strength, and muscle power. Data analysis procedures were as follows a) testing of construct validity of muscle function variables using confirmatory factor analysis (CFA) in SEM ; b) testing of causal structure using SEM ; c) testing of factor invariance using multi-group analysis for gender. The highest goodness of fit indices was obtained in the causal structure model of muscle, motor and living functions (NFI= .928, CFI= .978, RMSEA =.061) . The causal coefficient of muscle function to motor function was .98 (<I>p</I><.05), followed by.34 for motor function to living function. From the results of multi-group analysis, the measurement invariance model indicated the highest goodness of fit indices (TLI=.968, CFI .977) . It was concluded that the hierarchical causal relation was among muscle, motor and living functions, and in which muscle function was consisted of 3 sub-domains.