Meet the Team


A. LaCroix SheriHartman_03_Nov2011_sq.jpg D. Sears

Andrea La Croix - Principal Investigator of STAR, Principal Investigator of the P3 Project

Sheri Hartman - Principal Investigator of the P2 Project

Dorothy Sears - Principal Investigator of the P1 Project

Dr. LaCroix received her PhD in Epidemiology from the University of North Carolina at Chapel Hill and completed a postdoctoral fellowship in cardiovascular disease at The Johns Hopkins University. Dr. LaCroix came from the Fred Hutchinson Cancer Research Center, Public Health Sciences Division where she led many activities for the Women's Health Initiative Clinical Coordinating Center for more than 17 years. She was also a faculty member at the University of Washington (UW) from 1989 to 2013 and a Senior Scientific Investigator at the Group Health Research Institute.

Dr. Hartman is an Assistant Professor in the Department of Family and Preventive Medicine and in Cancer Prevention and Control at the UCSD Moores Cancer Center. She is also the co-leader of the UCSD Moores Cancer Center Diet and Physical Activity Shared Resource. Dr. Hartman is a clinical psychologist with extensive training and experience promoting health behavior change. Her research focuses on physical activity, weight loss, cognitive functioning and quality of life among cancer survivors as well as a variety of other patient and underserved populations.

Dr. Sears is an Associate Professor in the Department of Family Medicine and Public Health at UCSD. She is interested in translational and clinical studies of lifestyle behaviors that influence cardiometabolic disease and aging outcomes. With REACH she is the Community of Mine Study Lead for Biosecimens and Biomarkers; the Nucleotides to Neighborhoods Co-PI; and the Sedentary Behavior Studies Lead for Clinical Laboratory Studies and Biomarkers.

L. Natarajan    

Loki Natarajan - Principal Investigator of the Biostatistics Core



Dr. Natarajan joined the UCSD biostatistics faculty in 2002. Her methodological interests are in measurement error and validity, analysis of longitudinal time-series data obtained from sensors, and design and analysis of studies with multiple interrelated outcomes. When she is not immersed in statistical thought, she enjoys gardening especially with her feline companion, reading novels, and hiking. Dr. Natarajan is the Statistical Lead for REACH research projects.



D. Rosenberg S. Schenk M. Allison

Dori Rosenberg, PhD

Simon Schenk, PhD

Matthew Allison, MD

Dr. Rosenberg, PhD, MPH is an Assistant Investigator at Kaiser Permanente Washington Health Research Institute.  Dr. Rosenberg  has conducted extensive research into measuring and intervening on physical activity and sedentary time. Her research incorporates a multi-level and patient-centered perspective to help ensure individuals can be more successful in making healthy lifestyle choices.  Dr. Rosenberg has examined practical approaches to helping people sit less as an alternative strategy to health promotion. Through a series of iterative pilot studies, she has developed a sitting reduction intervention for older adults that is feasible and acceptable based on qualitative and quantitative findings. Furthermore, Dr. Rosenberg is helping to build an evidence base for the health effects of sedentary time. In the Adult Changes in Thought epidemiologic study, she is assessing physical activity and sedentary time with novel devices so she can examine associations with cognitive, functional and physical resilience.

Dr. Schenk, PhD, is an Associate Professor in the Department of Orthopaedic Surgery at UC San Diego. He is an exercise physiologist primarily interested in the regulation of substrate metabolism in skeletal muscle. The scope of his research is aimed at determining the impact of alterations in substrate metabolism, which may be induced via exercise, calorie restriction or inactivity, on important health issues such as obesity, diabetes, and advancing age.

Dr. Schenk is also interested in the etiology of fatty infiltration in skeletal muscle in orthopaedic-related injuries, such as rotator cuff tears and lumbar spine pathology.

Matthew A. Allison, MD, MPH is Professor and Interim Chief, Division of Preventive Medicine in the Department of Family Medicine and Public Health at the University of California San Diego. Dr. Allison earned his undergraduate degree in Biochemistry from the California Polytechnic State University and a Doctorate in Medicine from the Uniformed Services University. After medical school, and a categorical internship at the Naval Medical Center San Diego, he was trained and certified as a US Navy Diving and Undersea Medical Officer and then served in this capacity for 3 tours of duty.

J. Sallis    

Jim Sallis, PhD


James F. Sallis, PhD is newly appointed Distinguished Professor in the Department of Family Medicine and Public Health at University of California, San Diego. He also is Director of Active Living Research, a program of the Robert Wood Johnson Foundation. His primary research interests are promoting physical activity and understanding policy and environmental influences on physical activity, nutrition, and obesity.  He is the author of over 500 scientific publications, on the editorial boards of several journals, and one of the world's most cited authors in the social sciences.



Research Staff

L. Dillon    

Lindsay Dillon - Program Manager


Lindsay Dillon joined UCSD in 2003 as a Project Coordinator managing federally funded research projects related to physical activity, nutrition, weight management, sedentary behavior, and chronic disease prevention for pediatric and adult populations. Lindsay holds a Masters of Public Health from Emory University, where she also served as an intern at the Centers for Disease Control and Prevention working on physical activity environmental and policy projects.