Session perceived exertion (S-RPE) and session affective responses (S-AR) are post-exercise estimates of the global responses experienced during exercise. To compare S-RPE and S-AR to acute RPE (A-RPE) and acute AR (A-AR) during self-selected (SS) and imposed (IMP) exercise of the same workload. Thirty-two males (22.3 ± 2.2 years) performed two, 20-min cycle exercise trials. In the SS trial, subjects adjusted SS workload every 5 min. In the IMP trial, workload was automatically adjusted to the SS workload. Experimental (EXP, n = 16) subjects were unaware that workload was the same between the trials. Control (CON, n = 16) subjects were aware that both trials were of the same workload. A-RPE and A-AR were measured every 5 min using the OMNI Scale and Feeling Scale, respectively. Fifteen minutes following a cool-down, subjects rated S-RPE and S-AR. Session and exercise values were compared between trials and groups using ANOVA. No between-group differences were observed. There were no differences between the SS and IMP trials for S-RPE, A-RPE, S-AR and A-AR. For SS and IMP trials, S-RPE was greater than A-RPE (4.6 ± 1.5 vs. 3.9 ± 1.4; 4.3 ± 1.6 vs. 3.7 ± 1.4, respectively, p < 0.05). S-AR was greater than A-AR for the SS trial (1.9 ± 1.3 vs. 2.3 ± 1.5, p < 0.05), but not the IMP trial (1.9 ± 1.5 vs. 2.2 ± 1.4). A mismatch exists between the session and acute exercise values for RPE and AR during the SS cycle exercise in young males.