Motivated by personal experience navigating recreational sports systems in Toronto, this thesis explores how digital design can support sustained recreational sports participation among Gen Z and millennials. Using the Double Diamond methodology and iterative prototyping, the research investigates how principles from behavior change theory, gamification, and Self-Determination Theory (SDT) can inform digital interventions to enhance motivation, accessibility, and social engagement in recreational sports. Through a portfolio of four exploratory prototypes including community-building initiatives, motivational gamification strategies, and personalized goal-setting platforms, the project critically examines how UI/UX design can influence initial and ongoing participation. Findings highlight the importance of autonomy, peer support, and playful engagement in sustaining sports motivation, while also revealing the limitations of short-term interventions and the broader structural barriers beyond digital solutions. This research contributes to the growing discourse on digital activation in recreational sports by offering design insights for future tools that seek to support sustained participation through flexible, user-centered, and socially supported experiences.