Objectives:This study aims to (1) use the objective activPAL activity monitor to assess physical activity behaviors, including sitting/lying, standing, and both light (LIPA) and moderate-to-vigorous physical activity (MVPA); (2) to develop distinct activity profiles based on time spent in each behavior in a sample of adolescent females; and (3) examine whether levels of adiposity differ across these activity profiles.Methods:Female adolescents (n = 195; 14–18 y) had body mass index (median = 21.7 [IQR = 5.2] kg/m²) and 4-site skinfold thickness (median 62.0 mm; IQR = 37.1) measured. Physical activity behaviors were measured using the activPAL. Hierarchical cluster analysis grouped participants into activity profiles based on similar physical activity characteristics. Linear mixed models explored differences in body composition across activity profiles.Results:Three activity profiles were identified, a low (n = 35), moderate (n = 110), and a high activity profile (n = 50). Significant differences across activity profiles were observed for skinfold thickness (p = .046), with higher values observed in the low activity profile compared with the high activity profile.Conclusions:Profiling free-living activity using behaviors from across the activity intensity continuum may account for more of the variability in energy expenditure then examining specific activity intensities, such as MVPA alone. The use of activity profiles may enable the identification of individuals with unhealthy activity behaviors, leading to the development and implementation of more targeted interventions.