This study examined the patterning of acute affective responses to prescribed and self-selected exercise intensities in a young adolescent population. Twenty-two young adolescents (13.3 +/- .33 years) completed a maximal exercise test to identify ventilatory threshold (VT). Participants then completed two prescribed intensities (one set above and one below the VT) and a self-selected intensity. Pre-, during, and postexercise affective valence was measured. Results revealed that during exercise, affective valence assessed by the Feeling Scale (FS) remained positive in the self-selected and low-intensity conditions but declined in the high-intensity condition. Postexercise FS responses rebounded to preexercise levels, eradicating divergent trends that occurred during exercise.