Abstract
The importance of conceptual development for the translatability of study findings is well established (Lewin, 1947). For complex behaviours, such as physical activity (PA) participation, applying a theoretical framework can promote an understanding of causal mechanisms (Brown et al., 2013). The purpose of this systematic review is to examine the use of theory in PA interventions targeting children (aged 5 to 11 years) and adolescents (aged 12 to 17 years). A systematic search for randomized and non-randomized controlled interventions identified 128 studies (78 children; 50 adolescent) that met the selection criteria. Studies were coded as theory-based or atheoretical, and for the presence or absence of PA-related psychosocial outcomes. In children and adolescents, 59% and 78% of interventions were theory-based, respectively. The application of theory (?2 (1, N = 128) = 4.94, p < .05) and reporting on PA-related psychosocial outcomes (?2 (1, N = 128) = 4.39, p < .05) were significantly more likely to occur in interventions targeting adolescents compared with those targeting children. Of studies that reported on psychosocial outcomes, theory-informed interventions were significantly more likely than atheoretical interventions to report positive changes in adolescents (?2 (1, N = 30) = 10.43, p < .01) but not in children. Findings will be discussed within the context of PA-related psychosocial constructs and the paucity of data surrounding their measurement in children. This review supports a need for PA interventions targeting children to consider theoretical frameworks and theoretical constructs as mediators of PA behaviour change.
