To investigate the effect of physical exercise intensity on state anxiety symptoms and affective responses.

Twenty-one healthy women (mean age: 23.6 ± 5.4 years) participated in three sessions: self-selected intensity exercise, moderate-intensity prescribed exercise, and a nonexercise control session. Before each session, participants were exposed to unpleasant stimuli. State anxiety symptoms and affective responses were assessed pre- and post-stimulus exposure and pre- and post-sessions. A two-way repeated measures ANOVA tested state anxiety, while the Friedman test analyzed affective responses.

Time significantly affected state anxiety symptoms [F (2,0) = 25.977; P < 0.001; η2p = 0.565]. Anxiety increased post-stimulus (P < 0.001) and decreased after all sessions. No significant differences were found between exercise and control conditions. Time also significantly influenced affective responses [χ² (8.0) = 62.953; P < 0.001; Kendall’s W: 0.375]. Affective responses decreased post-stimulus (P = 0.029) and significantly increased after both exercise sessions (P < 0.001) but remained unchanged in the control session (P = 0.183).

Although state anxiety increased after unpleasant stimuli in all conditions, reductions following exercise sessions were comparable to the nonexercise session. However, both exercise sessions uniquely improved affective responses, highlighting their potential for emotional recovery after unpleasant stimuli.