running affective responses interaction synchronizationMusic is frequently utilized to enhance emotional states during physical exercise, potentially increasing engagement.Its influence may arise independently or through the interaction with exercise.However, the relative contributions of music's independent versus interactive effect on affective responses to exercise remain underexplored.To address this gap, fifty participants performed three tasks in a within-subjects design: a 35 minute affect-regulated intensity running with (C2) or without music (C1), and a seated control condition involving listening to the same music used in C2 without physical exercise (C3).We compared in-task affective responses (arousal and valence) and post-task emotional states.Results showed significantly higher arousal and valence ratings in C2 compared to C1.In these effects, only arousal ratings were influenced by the independent presence of music.Most of the observed differences, particularly enhanced valence, were attributed to the interaction between music and exercise.These findings suggest that self-selected music primarily enhances affective responses during affect-regulated intensity running through its interaction with exercise.