Understanding motivational dynamics: Longitudinal associations between motivation and physical activity in children

This study aims to test the longitudinal and reciprocal associations between autonomous and controlled motivation with physical activity (PA) behavior in children. These relationships were also inspected separately between boys and girls. A three-wave longitudinal study involving 502 children from primary school aged 9-11 years (M_age = 11.12; SD = 1.19; 160 boys [M_age = 10.53; SD = .53] and 131 girls [M_age = 10.49; SD = .53]), taking measures of each variable at three different times during nine months, was employed. Results indicated that boys' and girls' autonomous motivation was positively associated with higher PA behaviors over time. Furthermore, boys' and girls' controlled motivation was positively related with PA only at Time 2 (T2); however, it was negatively related only in girls at Time 3 (T3). Also, higher PA behaviors perceived by boys and girls at Time 1 (T1) showed a positive relationship with autonomous motivation at T2, as well as PA (only perceived with boys) at T2 and autonomous motivation at T3. Only PA at T1 showed a positive and significant relationship with controlled motivation at T2 in boys. To conclude, children who are autonomously motivated tend to sustain their participation in PA longitudinally, and vice versa; those children motivated by controlled factors are promoted to exhibit diminished interest in such activities over time.