Phdthesis.nl
Repository for several PhD. theses

Author: Maartje van Stralen

Title: THE ACTIVE PLUS PROJECT: changing physical activity behaviour in older adults

Details: The aims of the Active plus project described in this thesis were to develop and evaluate an intervention targeting physical activity behaviour among older adults. This thesis encompasses three main goals, which will be described, in line with the steps of the Model for Planned Promotion of Population Health, in three parts of this thesis: 1. Determinants of physical activity behaviour change First, this thesis aims to provide insight into the most relevant determinants of awareness, initiation and maintenance of physical activity behaviour older adults Specifically, Chapter 2 describes a review of the literature on the determinants of initiation and maintenance of physical activity behaviour among older adults. It is followed by Chapter 3 which describes a Delphi study conducted among national and international experts in order to identify the most relevant and modifiable determinants of awareness, initiation and maintenance of physical activity among older adults. 2. Development of interventions Second, based on research on the most relevant and modifiable determinants this thesis describes the systematic development of a theory and evidence‐based intervention targeting physical activity behaviour change among older adults. In Chapter 4 the systematic development of two tailored physical activity promotion interventions by application of the Intervention Mapping protocol is described. 3. Efficacy evaluation of intervention Third, the thesis encompasses the evaluation of the interventions by reporting on the effect and process evaluation using a randomised controlled design. In Chapter 5 the short‐term effects of the two intervention programmes on awareness, initiation and maintenance of physical activity are provided. Moderation analyses on baseline physical activity levels were performed in order to see if the interventions were as effective in stimulating initiation of physical activity among insufficient physically active participants as they were in stimulating maintenance of physical activity among sufficiently active participants. In addition a process evaluation is described in order to provide insight into the use and appreciation of the interventions. Chapter 6 describes the differences in short‐term effects of the two intervention programmes on different physical activity behaviours and the mediating mechanisms of environmental perceptions on the intervention effects. In Chapter 7 the long‐term effect and the mediating mechanisms of the intervention effect analysed in a single and multiple mediating models are described, aimed at identifying the working mechanisms of the interventions. Chapter 8, presents the long‐term efficacy of the intervention and its moderators, in order to identify who responded well or poorly to the interventions. The final chapter ‐Chapter 9‐ summarises the main findings of the thesis and discusses the implications for theory development, public health and future research.

Defense: Friday, 26 March, 2010 16:00