PROJECT SUMMARY/ABSTRACT Falls are the leading cause of injury-related death in older adults. With aging, gait becomes slower, more unstable, and more variable. Fall prevention interventions commonly target gait impairments as they are one of the strongest predictors of falls. Falls, however, encompass multiple risk factors including cognitive and environmental factors. While there is growing evidence that gait and cognition are related, there are limited longitudinal studies examining the association between gait and cognitive domains. In addition, there is limited knowledge of how older adults walk in everyday, naturalistic environments. Determining how gait, cognition, and environmental constraints are interrelated will enhance current fall prevention treatments through a multifactorial approach. Dr. Katherine Hsieh is a biomechanist by training with a strong background in measuring and quantifying gait and postural stability as it relates to falls. Her long term career goal is to develop tailored, targeted, and scalable fall prevention trials for older adults. This proposed F32 will provide her with cross-training in multiple fall risk domains including training in cognitive function and environmental constraints on gait. Dr. Hsieh will receive directed, hands-on training to achieve her 4 training objectives: 1) enhance knowledge of the relationship between cognition and gait; 2) enhance knowledge of environmental constraints on gait; 3) obtain training in clinical trials research; and 4) improve professional skills including manuscript writing, grant writing, and conference presentations. Her training plan includes didactic coursework, workshops, and seminars from Wake Forest School of Medicine. As part of Dr. Hsieh’s hands-on training, she will conduct secondary analysis of the Brain Networks and Mobility Function (B-NET) study of 240 older adults that included a battery of cognitive testing and gait measures collected at baseline and 18- and 30-month follow-up. Analysis will also be performed in a B-NET ancillary study of 90 adults completing everyday walking tasks in challenging environments with inertial measurement units. Dr. Hsieh’s research aims are to: 1) determine the association between cognitive function (executive function, processing speed, reaction time, inhibition) and gait (pace, rhythm, asymmetry, variability, stability) from baseline to 18- and 30-month follow-up, and 2) determine differences in gait smoothness and gait stability between older adults at high and low risk of Alzheimer’s disease and younger adults when walking over uneven surfaces and over obstacles. Dr. Hsieh will be mentored by an interdisciplinary team of leaders in aging research, including Dr. Denise Houston (physical function and falls), Dr. Christina Hugenschmidt (cognitive and brain function), Dr. Lisa Zukowski (environmental effects on gait), and Dr. Kristen Beavers (clinical trials design and execution). Ultimately, this proposed training plan and r...