We compared in-task affect to HIIE and MICE, and its relationship with time spent at different metabolic domains, perceived exertion (RPE), self-efficacy, enjoyment, and future intention of exercise in overweight inactive men. Muscle damage and soreness, and inflammation were assessed post-exercise. Fifteen participants (28.9 ± 5.0 yr; 29.2 ± 3.8 kg/m²) completed a HIIE (10 × 1 min at 100% V_max, 1 min recovery) and MICE (20 min at 55–59% VO_2reserve) session. Affect, alertness, RPE, and self-efficacy were assessed in-task, and enjoyment and future intention post-task. At baseline, 24 and 48 h, creatine kinase, lactate dehydrogenase, interleukin-6 and -10, tumor necrosis factor alpha, and muscle soreness were assessed. Affect (−3.1 ± 1.8 vs. 0.8 ± 1.8, P < .001) and self-efficacy (70 ± 15 vs. 90 ± 15%, P < .001) were lower, while RPE and alertness were higher in HIIE compared to MICE (Ps ≤ .02). Affect was negatively correlated with RPE in HIIE (r = −0.90) and MICE (r = −0.72), and time spent above respiratory compensation point in HIIE (r = −0.59). Affect was positively correlated with self-efficacy in MICE (r = 0.74). Enjoyment, future intention, muscle damage and soreness, and inflammation were similar between HIIE and MICE post-exercise. Therefore, in-task HIIE was experienced as unpleasant compared to MICE, but the psychological and physiological responses post-task were similar in overweight inactive men.