What are the circumstances which led you to your work?

My research on youth physical activity began when I arrived at my first job in the Department of Pediatrics at University of California, San Diego, where I started working with Philip Nader in 1983. I was enthusiastic about working on interventions to promote habits of regular physical activity early in life. Even after moving to the Department of Psychology at San Diego State University I continued and expanded my research on youth physical activity, most frequently with the collaboration of Thomas McKenzie.

Early training in Skinnerian principles of learning has influenced my continuing interest in environmental studies, because Skinner taught the environment influences behavior. Although training in environmental psychology would have been useful, I have not had that advantage. As I got more interested in physical activity while doing my post-doctoral fellowship with the Stanford Five-City Project, it seemed obvious that physical activity had to be done in specific places, and it might be informative to understand those places. For the next 15 years I made small efforts to incorporate environmental measures into various studies, but my skills in this area grew slowly. Contacts at CDC, such as Rich Killingsworth, Mike Pratt, and Tom Schmid, introduced me to people in related fields who clearly had much to contribute. The opportunity to direct the Active Living Research program for RWJF has allowed me to get more educated about relevant models and methods from diverse fields and to concentrate my effort on the environmental and policy work. The leadership of Katherine Kraft at RWJF and the expert contributions of Leslie Linton and Julie Weitzel make this work a pleasure.

  Would you describe the significance of this work for your field?

At the time I began studying physical activity and youth, there were few behavioral scientists working in the area, so there were many questions that needed to be answered. My colleagues and I have developed measures of physical activity and related psychosocial constructs and studied the correlates of physical activity that might inform intervention design. We have developed and evaluated physical activity interventions designed for families, elementary schools, middle schools, recreational facilities, and primary care clinics. We have published literature reviews, conceptual papers, and physical activity recommendations in an attempt to keep the research focused on issues with the most potential to contribute to increased activity among youth. The rising citation of this work is some indication that it is serving to advance science. I think it is more significant that the research has led to programs that are now being widely disseminated (www.sparkpe.org) and is being used by groups around the world to help guide their plans for youth physical activity promotion, such as an ambitious effort in Nova Scotia, Canada.

My enthusiasm for the environmental work leads me to believe that the entire field of environmental and policy studies in physical activity is likely to influence research in disparate fields and lead to improvements in public health. The obesity epidemic is creating a need for approaches that can realistically change behavior on a population-wide basis for the long-term. The implication from ecological models is that the most effective approach will be to create environments that make it easy for people to make healthful choices, then motivate people and teach them skills to make those choices. This hypothesis is quickly becoming accepted in the health behavior field, which is a big change from 10 years ago. We are now at the point where hypotheses derived from ecological models need to be tested, and the Active Living Research program is funding such studies. Moreover, our team has been fortunate to obtain funding from the National Heart, Lung, and Blood Institute to conduct our own study of the links between environments and physical activity (www.nqls.org). Key members of the team are Larry Frank, Brian Saelens, Kelli Cain, and Terry Conway. We are using objective measures of environments and physical activity to study people in two regions of the nation. We hope this study contributes to a new paradigm that integrates the skills of multiple disciplines to simultaneously investigate psychological, social, environmental, and policy correlates of health behavior that can inform policy change.

  Where do you see this research going 10 years from now?

The current studies are identifying environmental factors, policies, and programs that seem to be effective in increasing physical activity. The next priority is to conduct studies that will help us move this knowledge into practice. That includes diffusion of effective programs, studying the policy change process, and evaluating advocacy efforts to change policies. Another need is to coordinate international studies that could lead other countries to avoid the worst of the conditions that are contributing to the obesity epidemic in the U.S. These studies are more complex than evaluating individually-based educational programs, will require our teams to expand to include new disciplines, and are likely to challenge funding agencies, but these are the studies needed to create more active populations.

  What lessons would you draw from your work to share with the next generation of researchers?

First, spend some time and effort to identify research questions that have the potential to contribute to solutions for the biggest or most difficult societal problems. Second, if you believe your work is truly important, then stick with it, even though others do not agree. Time will tell who is correct. Third, I am convinced of the superiority of cross-disciplinary collaboration, so make it a point to learn what other fields can contribute to your work, and develop collaborations with excellent people from those fields.