Sedentary behavior is detrimental to body composition in older adults and a possible predictor for cardiometabolic disease. PURPOSE: To validate the correlation between levels of physical activity and body composition in older adults. METHODS: Activity levels from five days of accelerometer data of 315 subjects (mean age: 63.47 ± 5.90 years, mean BMI: 27.91 ± 4.54 kg·m^-2 male: 155; female: 160) were retrieved from the Interactive Diet and Activity Tracking in AARP (iDATA) database from the National Cancer Institute. Subjects were also categorized into three body composition (BMI) subgroups: normal (<18.5-24.9 kg·m^-2), overweight (25-29.9 kg·m^-2) and obese (>30 kg·m^-2). Average time spent (secs) in standing, sitting, lying and number of steps for each subject were measured. Descriptive statistics were performed for the entire sample and all three subcategories. Analysis of variance (ANOVA) between the three groups were performed for weekly steps and time spent standing, sitting, and lying down. An alpha level of .05 was considered statistically significant. A linear regression analysis was performed to explore the association between these variables and body composition for the entire sample. RESULTS: ANOVA analysis revealed statistically significant differences for time spent standing and sitting between the normal weight (standing: 26,941 ± 8,163 secs; sitting: 29,954 ± 9,197 secs) group and the overweight (standing: 22,840 ± 7,892 secs; sitting: 33,632 ± 10,630 secs) and obese (standing: 20,836 ± 7,318 secs; sitting: 34,467 ± 10,335 secs) groups. The regression analysis showed a statistically significant association (r=.31, r2 =.094; p < .001) among steps, standing, sitting, and lying with the greatest contributors to the model being standing time (p=.008) and sitting (.042). The greater time standing indicated lower BMI, while greater time sitting contributed to greater BMI. CONCLUSIONS: In older adults, greater time spent standing and lower time spent sitting appears to be the greater contributors for desirable body composition. This population of adults should be encouraged to spend more time in standing activities to enhance their health and wellness for a more desired cardiometabolic profile.