This study drew upon an ecological system framework to examine a model focusing on the interrelationship among depressive symptoms, sense of mastery, moderate-to-vigorous physical activity (MVPA), religiosity, and relations with parents and romantic partners among U.S. young adults aged 24 to 34. Cross-sectional data from the National Longitudinal Study of Adolescent Health (N = 4,982), obtained in 2008 and 2009, were analyzed using structural equation modeling techniques. The associations of MVPA, relations with parents, and relations with romantic partner to depressive symptoms were mediated through mastery. Relations with one's romantic partner were a stronger predictor of depressive symptoms than relations with parents, while the influence of religiosity on relations with romantic partner was largely mediated by relations with parents. The results highlight the sociobehavioral buffers of depressive symptoms that are peculiar to young adulthood. Further intervention research in preventing and treating depressive symptoms should consider incorporating the sociobehavioral factors that are tailored to the specific age group.
Keywords: depressive symptoms; mastery; physical activity; relations with parents; religiosity; romantic relationships.