In the past decade, the number of children diagnosed with an autism spectrum disorder (ASD) has steadily increased. A common characteristic of ASD is the presence of stereotypical behaviors (e.g., hand flapping, echolalia), which some have suggested may be associated with heightened arousal and/or anxiety. The purpose of this study is to compare antecedent interventions that have been used to decrease stereotypical behaviors in three elementary students with ASD by modulating arousal. Using a single-case alternating treatments design across participants, we compared the relative efficacy of antecedent exercise with two forms of deep-pressure therapy (DPT; compression vest and weighted blanket). Results of the current study found mixed effects for the interventions, with DPT providing little reduction of stereotypical behaviors and antecedent exercise (riding a stationary bike) providing improvement in two of three cases. Implications for practitioners and future research are provided.