Dr. Ashley Cooper
Department of Exercise, Nutrition and Health Sciences
University of Bristol
Bristol, UK
http://www.bris.ac.uk/enhs/peach
Project title (1)
Personal and Environmental Determinants of Eating Behaviours and Obesity in Adolescents (PEACHEB) (2007/41)
Project title (2)
PEACH: Personal and Environmental Determinants of Children's Health (R2010/258)
Scientific abstract 1
This study will investigate the associations between personal, social and environmental characteristics and eating behaviours. The main hypothesis for this study is that the environment (physical, home or school) in which a young person lives is associated with consumption of healthy or unhealthy foods and their level of physical activity. The secondary hypothesis is that these factors are associated with obesity and that change in consumption of healthy/unhealthy foods and/or physical activity level is related to change in obesity status. The study will measure a wide range of environmental correlates of eating and physical activity behaviours, and generate a theoretical model of how the key behaviours interact to help to explain their association with obesity.
One thousand students will be recruited in their first year of secondary school and followed up two years later. At each time point physical activity will be measured with accelerometers. Participants will wear GPS receivers to record journeys to and from school and at lunchtime and will complete computerised questionnaires to measure personal, social and environmental factors believed to be associated with eating behaviours, physical activity and obesity. GPS data will be used within geographical information systems to characterise the proximity, number and type of food outlets visited, providing an objective measurement of the interaction of participants with the physical environment.
Scientific abstract (2)
Background: In adulthood, being overweight or obese increases the risk of many cancers. Overweight and obesity are at high levels among youth and are liable to precede overweight and obesity in adult life. Preventing childhood obesity is therefore essential for the long term prevention of adult cancer.
Identification of the modifiable factors in youth that may lead to the development of obesity is therefore essential to finding ways to prevent obesity and cancer risk. One such factor is physical inactivity, which has been associated with obesity in both adults and children. Fruit and vegetable consumption is associated with lower levels of obesity among adults and children, and epidemiological studies show an inverse relationship between dietary intake of fruit and vegetables and incidence of cardiovascular disease, stroke and cancer in adulthood.
Despite these benefits, many children and adolescents have levels of physical activity and fruit and vegetables consumption below recommended guidelines. In this application we will also explore a potential mechanism by which environmental stress may influence the development of obesity with a focus on whether the stress hormone cortisol functions as a mediator in the relationship between behaviours and obesity.
Objectives:
- To reliably characterise the physical activity levels and patterns of young people in their fourth year of secondary school.
- To describe what aspects of the real or perceived physical environment are associated with eating and physical activity behaviours.
- To use GPS and GIS technology to identify key locations where physical activity takes place.
- To determine whether the above factors differ by gender and social position.
- To describe the relative contributions of environment, psychosocial and demographic variables to physical activity and eating behaviours.
Additional objectives within the new study are:
- To measure daily cortisol levels in a substantial cohort of adolescents to determine whether they are associated with overweight or obesity, physical activity or eating behaviours, the physical environment, social position or environmental stressors.
Setting and methods: Over 1300 young people have already been recruited to the first phase of this study whilst in primary school. 953 of these have also been followed up in their first year of secondary school. This study will measure the children again now that they are 14 years old.
This will allow us to investigate whether changes in physical activity and eating behaviours that we discovered between primary and secondary school are continued into later adolescence. They will have their activity measured with activity monitors, will wear GPS receivers to record journeys to and from school and in the evening, and will complete computerised questionnaires to measure personal, social and environmental factors believed to be associated with eating behaviours, physical activity and obesity. On one day they will provide a saliva sample 5 times during the day for measurement of cortisol.
Potential impact: Few if any existing data sets have measured the wide range of personal and environmental variables available in PEACH, and this study thus provides a unique opportunity to investigate how longitudinal changes in health behaviours and obesity are associated with environmental variables.
The integration of neuroendocrine processes e.g. increased cortisol secretion, into traditional models of obesity holds promise for illuminating mechanisms by which physiological processes may influence the development of obesity and indicates new directions in understanding and preventing childhood obesity.
Project 1 plain language abstract
Overweight and obesity in the young are increasing rapidly, and the environment is believed to play a role in this. However there are few data that describe how the environment may influence eating behaviours or physical activity. The main hypothesis for this study is that the environment (physical, home or school) in which a young person lives is associated with consumption of healthy or unhealthy foods and/or their level of physical activity, and that these factors are associated with obesity. Our objective is to measure a wide range of environmental correlates of eating and physical activity behaviours, and to generate a theoretical model of how the key behaviours interact to help to explain their association with obesity. One thousand students will be recruited in their first year of secondary school and followed up two years later. They will have their activity measured with activity monitors, will wear GPS receivers to record journeys to and from school and at lunchtime, and will complete computerised questionnaires to measure personal, social and environmental factors believed to be associated with eating behaviours, physical activity and obesity.
Project 2 plain language abstract
Background: Overweight and obesity in the young are increasing rapidly, and the environment is believed to play a role in this. However there are few data that describe how the environment may influence physical activity or eating behaviours.
Aims & goals: The main hypothesis for this study is that the environment in which a young person lives is associated with their level of physical activity and/or consumption of healthy or unhealthy foods, and that these factors are associated with obesity. Our objective is to measure a wide range of factors known to be associated with eating and physical activity and to describe they interact in the development of obesity. In addition we will investigate how stress due to poor living environments may be related to a hormone called cortisol, that is released due to stress and is associated with obesity.
How it will be done: Over 1300 young people have already been recruited to the first phase of this study and will be followed up again now that they are 14 years old. This will allow us to investigate whether changes in physical activity and eating behaviours that we discovered between primary and secondary school are continued into later adolescence. They will have their activity measured with activity monitors, will wear GPS receivers to record journeys to and from school and in the evening, and will complete computerised questionnaires to measure personal, social and environmental factors believed to be associated with eating behaviours, physical activity and obesity. On one day they will provide a saliva sample 5 times during the day for measurement of cortisol.
Potential impact: This study will describe how children interact with the environment and how this may influence physical activity, eating behaviours and obesity. This information will allow us to design interventions to help prevent childhood obesity.
| Institution and location | Degree | Year | Scientific field |
|---|---|---|---|
| University of Bristol | BSc | 1978 | Cellular Pathology |
| University of London | PhD | 1983 | Developmental Biology |
| Imperial College London | MRC training fellowship | 1986 | Molecular Biology |
| University of Bristol | MsC | 2000 | Exercise and Health |
| 2008 - Present | Reader in Exercise and Health Science, Department of Exercise, Nutrition and Health Sciences, University of Bristol |
| 2004 – 2008 | Senior Lecturer & Head of Exercise, Nutrition and Health Sciences, University of Bristol |
| 1997-2004 | Lecturer, Exercise and Health Sciences, University of Bristol |
| 1995-1996 | Research Assistant, Exercise and Health Sciences, University of Bristol |
Research interests
Measurement of physical activity and determinants of physical activity in children and adolescents.
