Regular physical activity protects against cellular aging, but a recent study found shorter telomere length (TL) in professional swimmers compared to less active controls. Shorter TL is associated with increased cellular senescence and functional decline with age, suggesting swimmers may be at increased risk for age-related morbidity. Previous studies reported competitive swimmers face high levels of psychosocial stress, which, in turn, are posited to accelerate TL shortening. We hypothesize that competitive collegiate swimmers experience increased psychosocial stress, leading them to have shorter TL despite their active lifestyles. We are conducting a mixed-methods study to examine whether TL differs between Division-1 and Division-3 NCAA swimmers (N=28 respectively) and their non-athlete counterparts (N=15) and if differences in TL is associated with psychosocial stress (Total N=43). Collegiate swimmers face a unique set of stressors to perform for scholarships and professional opportunities while simultaneously continuing their responsibilities as students. Accordingly, we are measuring overall psychosocial stress (Cohen’s Perceived Stress Scale; PSS) to compare swimmers and non-athletes as well as sports-related psychosocial stress (The Student Athletes’ Motivation toward Sports and Academics Questionnaire; SAMSAQ) to compare D-1 to D-3 swimmers. Further, we are conducting semi-structured qualitative interviews to better contextualize how student-athletes perceive how the psychosocial stress they experience impacts their lives and performance. We expect swimmers to report higher levels of overall psychosocial stress (PSS) and have shorter TL compared to non-athletes. Further, we expect that D-1 swimmers will report higher levels of psychosocial stress (SAMSAQ) and have shorter TL compared to D-3 swimmers.