Date of Submission



Introduction: Extensive research has supported the physical and psychosocial health benefits of physical activity among typically developing youth. These benefits include higher quality of life, lower risk of disease, higher levels of psychological and emotional well-being, greater school engagement, greater motor skills, more frequent prosocial behaviours, and enhanced self-concept. Compared to their typically developing peers, youth with intellectual disability participate less frequently in physical activity, tend to be less fit, have poorer motor control, and worse mental health. Many studies examining sport and physical activity for youth with disability have focused on a limited range of outcomes or interventions, have not specifically focused on youth with intellectual disability, or examined the prevalence of physical activity and sport behaviours rather than their outcomes and determinants. Therefore, the primary objectives of this thesis were to: (1) Examine the physical and psychosocial health outcomes of physical activity among youth with intellectual disability, and (2) identify potential determinants of sport participation for adolescents with intellectual disability. Methods: This thesis includes a systematic review with two meta-analyses (Study 1) and a longitudinal study conducted over two years (Study 2). Using a three-level, random-effects and mixed-effects meta-analytic approach, results from 109 studies that included 810 effects of physical activity on either physical or psychosocial health outcomes were explored. The longitudinal study included a sample of 252 Australian adolescents with intellectual disability (M = 14.98 years, SD = 1.85) at Time 1. At each of the three timepoints, participants completed questionnaires assessing their sport participation, physical self-concept, intrinsic motivation, and worries. They also completed a physical fitness test assessing cardiovascular fitness. Results: The systematic review and meta-analyses found that physical activity has positive effects on the physical and psychosocial health of youth with intellectual disability. Resistance training shows the most physical benefits, while teaching movement and sports skills appears to improve both physical and psychosocial health. The results from the longitudinal study suggested that physical self-concept may be a determinant of sport participation; however, sport participation did not appear to predict worries or cardiovascular fitness. Conclusion: The systematic review and meta-analyses included in this thesis represent the first quantitative synthesis of research focused on the physical and psychosocial benefits of physical activity for youth with intellectual disability. It is promising that this review points to physical activity as a method of improving the physical and psychosocial health of youth with intellectual disability. While the meta-analyses suggested that sport and sport skills training were the most beneficial for of physical activity for this population, the longitudinal study did not support these findings. The longitudinal study, however, did suggest that promoting physical self-concept may help to increase sport participation among youth with intellectual disability.


Institute for Positive Psychology and Education

Document Type


Access Rights

Open Access


182 pages

Degree Name

Doctor of Philosophy (PhD)


Faculty of Health Sciences