Influence of Physical Self-Concept and Motivational Processes on Moderate-to-Vigorous Physical Activity of Adolescents.

There is a growing concern about the increasing decline in physical activity among adolescents. In the search for variables that may be related to physical activity, this study examined the influence of physical self-concept on objectively measured moderate-to-vigorous physical activity (MVPA) of adolescents through the mediation of the needs satisfaction and two types of autonomous motivation, for academics and for physical education. Data were collected from 618 students (301 boys and 317 girls) aged 10-14 years from 24 secondary schools in Spain. The path analysis results showed that physical self-concept positively predicted needs satisfaction and this, in turn, was positively and significantly related to the two types of autonomous motivation. Finally, only the autonomous motivation for physical education significantly and positively predicted the adolescents' MVPA. Our findings showed that there was no evidence of an indirect effect of physical self-concept on MVPA. The results are discussed along the lines of the self-determination theory, through the analysis of the role of physical self-concept in increasing adolescents' physical activity.