The EAST Study aims to uncover whether a single bout of aerobic exercise can mitigate responses to an in-lab stressor. Research shows that leading an active lifestyle can reduce levels of psychological and biological stress in daily life. Less is known, however, regarding the effects of a single bout of exercise on the biological and psychological stress response. In this study, participants will perform various intensity exercise in our lab and then perform a brief public presentation; psychological assessments and biological samples from saliva are acquired in order to gauge individuals’ responses. The study aims to reveal psychobiological mechanisms that explain the complex relationship between exercise and stress.