This thesis has two purposes: firstly, to develop grounded theory methodology and secondly, to apply it in order to establish and further investigate those processes which structure young peoples' participation in physical activity. To satisfy the first of these aims, the Helix Model was created to provide a systematic framework to the grounded theory analysis. This Model was then employed to address the second aim, as it was used to analyse interviews conducted with a mixed sex sample of twenty nine very active and very inactive children and their parents. These young people were selected as a result of completing, on four occasions, a 24 hour self-report questionnaire specifically designed for them. The grounded theory analysis identified a series of interrelated 'gatekeeping processes' which construct those opportunities for young people to participate in physical activity. Several evolving processes, varying according to the context and nature of the physical activity, interrelate with one another to create a complex causal web. The gatekeeping processes are consciously, as well as unconsciously, manipulated relative to the social and physical context in which the young person and the other gatekeeping agents (parents, school, peers) exist and find themselves. The interrelationships between these agents, especially the young person and their parents, work through compromise and coercion to satisfy each of their personal agendas. The nature of each agenda is based on the definition associated with the three roles which gatekeepers adopt (guardian, facilitator, enforcer). The definition of each role affects the manner in which young people individually, as well as collectively with the gatekeepers, construct networks to accomplish an evolving combination of: independence, maximisation of the available resources, rewards, and care and control. The interrelationship between these factors and the extent to which participation in physical activity can achieve them, is what determines the likelihood of the young person's participation in that activity. However, physical activity has to compete with a myriad of the other activities the young person is involved in. These are activities, which for the more sedentary young person, are perceived to be more successful at providing the desired rewards.

Lately both scientists and news reports have indicated increased concerns that parent-spectator behavior at youth sport events may be problematic. The overall purpose of this study was therefore to examine what behaviors adult spectators show during 10-12 years old girls participation within the sports football and equestrian. Data for the study was assembled by the writers in form of on site, non-participating observations. A total of four observations took place, two within each sport, during which the adult spectators behaviors was noted and studied in relations to norms and environmental effects. Results indicate that regardless of the different characters of the sports there are no significant differences in shown behavior. Most adult spectators exhibit behaviors which in relation to the study's theory is to be considered appropriate for the girl’s sport participation. Some exceptions were observed, adult spectators that exhibited behaviors less appropriate for the girl’s sport environment, but the amount in which these behaviors were shown is not on its own enough to be considered alarming.Lately both scientists and news reports have indicated increased concerns that parent-spectator behavior at youth sport events may be problematic. The overall purpose of this study was therefore to examine what behaviors adult spectators show during 10-12 years old girls participation within the sports football and equestrian. Data for the study was assembled by the writers in form of on site, non-participating observations. A total of four observations took place, two within each sport, during which the adult spectators behaviors was noted and studied in relations to norms and environmental effects. Results indicate that regardless of the different characters of the sports there are no significant differences in shown behavior. Most adult spectators exhibit behaviors which in relation to the study's theory is to be considered appropriate for the girl’s sport participation. Some exceptions were observed, adult spectators that exhibited behaviors less appropriate for the girl’s sport environment, but the amount in which these behaviors were shown is not on its own enough to be considered alarming.