Abstract
Adolescence is a pivotal developmental stage characterized by heightened vulnerability to stress and rapid fluctuations in emotional well-being. Using a 30-day daily diary design on 107 adolescents (11–18 years old; M
age = 14.75, SDage = 1.59; 38.3% female, 58.9% male), this study examined both same-day and lagged-day associations between daily stress and adolescent emotional well-being (positive and negative affect) and explored the moderating roles of sport experience and sleep quality in buffering the aversive effects of stress. Results revealed both same-day and lagged-day effects of daily stress on adolescent emotional well-being. In addition, sport experience moderated the same-day stress-affect associations, supporting the same-day buffering hypothesis; it also moderated the associations between stress and lagged-day affect, supporting the recovery hypothesis. Similarly, sleep quality the night before stress exposure moderated the same-day stress-affect associations, supporting the preparation hypothesis; sleep quality the night after stress exposure moderated the associations between stress and lagged-day affect, supporting the reset hypothesis. Findings underscore the importance of disentangling dynamics in daily stress-affect associations, and demonstrate the effectiveness of promoting positive sport experience and sleep quality to enhance adolescent emotional well-being. Implications for interventions and future research directions are also discussed.