Psychosocial correlates of physical activity among fifth and eighth graders.

BACKGROUND: Identification of the factors that influence children's participation in vigorous activity is essential to the development of effective intervention strategies aimed at the prevention of cardiovascular disease and obesity.
METHODS: Correlates of intent to participate in vigorous activity were assessed among 310 fifth and eighth graders in Cambridge, Massachusetts, through the development and administration of a questionnaire based on the Theory of Planned Behavior, an extension of the Theory of Reasoned Action, which includes the domain of perceived behavioral control (how easy or difficult it is to engage in vigorous activity). Heights and weights were measured and questionnaires were completed during physical education classes.
RESULTS: Perceived behavioral control and attitude predicted children's intent to participate. How much a child agreed s/he was good at doing vigorous activity predicted perceived behavioral control. In each grade, girls reported being less good at vigorous activity than did boys. Eighth-grade girls reported significantly fewer hours of vigorous activity than did eighth-grade boys.
CONCLUSIONS: Our findings suggest that gender differences related to intent to participate in vigorous activity, perceived behavioral control, and sense of competency are evident in eighth grade and may begin in fifth grade. These gender differences in perception therefore precede the gender difference in participation in vigorous activity demonstrated among ninth graders in the 1990 Youth Risk Behavior Survey. Promotion of activities children enjoy, and in which they feel a sense of competency, is likely to sustain participation in vigorous activity throughout adolescence and possibly reduce the prevalence of obesity.