PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

The present study was undertaken to examine the roles of social supports on adolescents' involvement in outof-school physical activities. 175 conveniently sampled middle high school students from three public schoolsin Western Australia participated in this study. Data were collected using self-report measures of physicalactivity (PA) duration, social support (modelling, instrumental, and motivational supports) and social supportagents (mother, father, siblings, peers, and teachers). Using stepwise regression analysis, the results revealedthat motivational and instrumental supports were significant predictors of the PA for the male and femaleadolescents, respectively. In terms of the roles of social agents, father was indicated as an influential agent of change for the male adolescents, while mother and peers were influential figures for the female adolescents' involvement in physical activity. The finding of this study reinforces the view that social support for PA maybe best provided by the adolescents' same-sex parents. The finding also supports the notion that motivationaland instrumental supports may be more effective in promoting male and female adolescent PA, respectively.