An attempt was made to determine if state anxiety responses following acute exercise are influenced by the intensity of exercise. Fifteen adults (5 female, 10 male) completed 20 minute sessions of bicycle ergometer exercise on separate days at intensities equal to 40, 60, or 70% VO2peak. Expired gas spirometry was employed to determine peak oxygen consumption and to control the workload during the submaximal protocols. State anxiety (STAI-Y1) was assessed prior to and following each exercise session, and 5, 60 and 120 minutes post-exercise. Repeated measures ANOVA revealed that state anxiety decreased (p < 0.05) following each exercise condition. Post hoc analysis indicated that state anxiety was significantly (p < 0.05) reduced at all post-exercise assessments in the 40 and 60% VO2peak conditions. State anxiety was elevated by 3.4 units at 5 minutes following exercise at 70% VO2peak, but decreased (p < 0.05) below baseline at 60 and 120 minutes post-exercise to a degree not different from the other exercise conditions. Further analysis indicated the increase in anxiety 5 minutes following 70% VO2peak exercise was significant only in subjects with low baseline state anxiety values, whereas it was unchanged in subjects with higher baseline values. In conclusion, 20-minute sessions of cycle ergometer exercise at intensities ranging from light to heavy were equally effective in reducing state anxiety in young, healthy adults. However, this reduction is delayed somewhat following exercise at a high intensity (i.e., 70% VO2peak).