abstract: This study examines the one month retention of executive function benefits gained by adolescents with Down syndrome after an 8-week aerobic exercise intervention. Sixteen participants were randomly divided between voluntary (VC) (i.e., self-selected cadence) and assisted (AC) (i.e., 30% faster than self-selected cadence accomplished by a motor) cycling groups, with one participant used as a control (NC). Both cycling groups rode a stationary bicycle, for 30 minutes, three times a week, for eight weeks. At the beginning (i.e., pretest) and end (posttest) of the 8-week session, three executive functions including: set-switching, inhibition, and cognitive planning, were tested. Approximately one month after the posttest, all particip...