https://www.selleckchem.com/products/yo-01027.html disability in older adults. Frailty phenotype has been extensively modified. Among the five criteria, the low physical activity (PA) is often changed, however, it is still uncertain how this modification might impact frailty classification. To examine the variance in the prevalence of frailty by modifying PA criterion using different cut-points of both subjective and objective measures, and to determine the agreement between these on classifying individuals with low PA. Finally, a surrogate PA criterion of frailty phenotype was proposed using objectively measured moderate-to-vigorous physical activity (MVPA). This cross-sectional study comprised a convenience sample of 135 community-dwelling older adults. Frailty was evaluated using a modified frailty phenotype. PA was assessed using International Physical Activity Questionnaire-short form (IPAQ-SF) and objectively measured using a uniaxial accelerometer for 7 days. Four different low PA criteria were created and compared (population dependent and independent cut-points) using sub.Background Ageing-related muscle atrophy does not occur uniformly across the body; rather, atrophy occurs to a greater extent in specific muscle groups compared to others. However, site-specific comparisons of muscle mass between older and younger adults typically do not account for relative muscle mass (i.e., matched for age- and ***-specific percentiles), which may confound site-specific differences. Furthermore, the uniformity of ageing-related differences in muscle composition (e.g., intramuscular adipose tissue) across the body are not well characterized. Purpose To examine site-specific muscle mass and composition differences between younger and older males matched for relative muscle mass. Methods Younger (18-44 years old, n = 19) and older (≥65 years old, n = 19) males were matched for relative appendicular lean tissue index (NHANES age- and ***-specific Z-scores) measured using du