The purpose of this study was to examine the validity of a modified Assisted Cycling Therapy bicycle for improving depression in children with Down Syndrome (DS). Seven participants completed 2x/week for 8 weeks, 30 minutes at a time of ACT, in which participants’ voluntary pedaling rates were augmented via the bicycle motor, ensuring that they were pedaling at a rate greater than their self-paced rate. Depression was measured using a modified version of the Children’s Depressive Inventory, called the CDI-2. Our study demonstrated that the scores from the CDI-2 decreased, demonstrating less depressive symptomatology after the conclusion of the 8 week intervention. Our results were interpreted via our model of the mechanisms involved in influencing the success of ACT. Future research would include a greater sample size, a more relevant measure of depressive scores, and a consistent data collection environment. However our initial pilot study showed promising results for improving mental health in children with DS.