Stereotypic behaviors, characterized by persistent repetition of actions without an obvious goal,are often observed in captive animals but not in their wild counterparts. Voluntary wheel runningin captive rodents is one such behavior, potentially indicative of stereotypy. This study exploresthe hypothesis that selectively bred high runner (HR) mice, known for their extreme levels ofwheel running, also exhibit higher levels of other stereotypic behaviors compared to non-selectedcontrol (C) lines. Behavioral observations were conducted on both HR and C lines to quantifystereotypic behaviors. Additionally, the impact of environmental enrichment (addition of acardboard toilet paper tube to the cage) on these behaviors was assessed. When housed withwheels for six days, HR mice had significantly higher levels of both wheel running and otherstereotypic behaviors compared to C mice. With the introduction of enrichment, wheel runningby HR mice increased during the next 24 hours, whereas wheel running by C mice did notincrease. These findings provide insights into the genetic and environmental factors influencingstereotypic behaviors and highlight the potential of HR mice as a model for studying humanstereotypic behavior.