A home-based intervention to improve adherence to the 24-Hour Movement Guidelines in young children - PROJECT SUMMARY Few young children meet the recently adopted World Health Organization recommendations for movement behaviors (physical activity, sleep, and screen-time), known as the 24-Hour Movement Guidelines. This inadequate balance of movement behaviors places children at risk for more behavioral problems, poor cognitive development, delayed motor skills, and obesity. Minority children and children who live in low-income household are at increased risk of meeting few recommendations, and consequently these long-term health outcomes. Pitfalls of current literature include focusing on one behavior at a time and neglecting the context in which these behaviors occur. Ecological momentary assessment (EMA) and mHealth tools are ideally positioned to address this gap, by assessing and addressing movement behaviors in real-time and within the home, where all three movement behaviors occur. Using mixed methods, this study aims to identify patterns (amount and context) of child movement behaviors within the home via EMA paired with a child-worn accelerometer and identify barriers and facilitators to changing these behaviors within the home via semi-structured interviews (Research Aim 1). Behavior change theory, previous literature, and an iterative process using parent feedback will inform the design of a movement behavior intervention delivered through a mHealth modality (e.g., mobile app, Research Aim 2). Finally, this study will then pilot test the preliminary effectiveness and feasibility of this intervention in a randomized control trial with the goal of meeting all three movement behavior recommendations, thus the 24- Hour Movement Guidelines (Research Aim 3). To complement these research aims, the candidate will receive didactic, hands-on, and applied research training in EMA, mHealth, and interventional research amongst diverse populations (Training Aim 1), along with behavior change theory and child behavior and cognitive development (Training Aim 2). The candidate will expand her network and presence, and scientific prowess in writing grants and mentoring to propel her into a future career as a 24-Hour Movement expert (Training Aim 3). Experts in these respective fields, who are also seasoned mentors, will guide her through these research and training aims, and ultimately into an independent position and research career. This experience will culminate in data for the candidate to build her independent research program, with the goal of improving child movement behaviors, and ultimately their long-term health.