While affective responses to aerobic exercise are fairly well documented, only recently have affective responses to high-intensity interval exercise been examined. PURPOSE: To evaluate affective responses before, during, and following, as well as enjoyment following aerobic and higher intensity interval exercise, along with a sedentary control. METHODS: Participants (N =207; 111 female; 20.4±2.6 yrs, M±SD) completed randomly ordered 15-min conditions: walking (W; avg RPE=8.4), reading (R), high-intensity cardio resistance (HICR; avg RPE=14.1; 2 min activity, 1 min recovery). Affect (Energy, Tiredness, Tension, Calmness) and state anxiety (SA) were assessed before (Pre), immediately after (P0), and 20 min after (P20) each condition; enjoyment (Physical Activity Enjoyment Scale) was measured post exercise only. Affective valence (Feeling Scale; FS) was assessed Pre, every 3 min during, and P20. RESULTS: Affect and SA changed from Pre to P0 with Condition x Time interactions (all Ps< 0.001) for all measures, reflecting improved affect following HICR and W relative to R. Affective valence (i.e., FS) progressively decreased during HICR: by P0 it was less positive than Pre (Mdiff±SE= -0.49±0.20, P= 0.014), then rebounded at P20 to be greater than Pre (0.66±0.13, P< 0.001) and P0 (1.15±0.15, P< 0.001). FS also decreased during R, with P0 FS being less positive than Pre (-0.66±0.11, P< 0.001) and P20 (-0.27±0.09, P= 0.003). During W, FS increased from Pre to P0 (0.55±0.13, P< 0.001) and remained elevated at P20 (0.75±0.11, P< 0.001). Enjoyment was greater following HICR (92.31±19.55) than both W (88.21±17.61; P= 0.025; d= 0.22) and R conditions (53.03±18.47; P< 0.001; d= 2.07); W resulted in greater enjoyment than R (P< 0.001; d= 1.95). Further, after accounting for age, sex, and Pre FS, FS during each condition (i.e., average across 5 assessments) predicted unique variance in enjoyment (HICR: 31.5%; W: 32.5%; R: 22.6%; all Ps< 0.001). CONCLUSION: These findings extend previous research by examining affective responses to aerobic and high-intensity interval exercise plus a sedentary control. The findings suggest the HICR exercise used here may elicit more enjoyment than continuous low intensity exercise. This also highlights the importance of in-task affect for predicting exercise enjoyment.