Physical inactivity is a one of the leading health risk behaviors related to the global epidemic of obesity and chronic diseases such as diabetes and heart diseases. The increasing number of young people being inactive is therefore discouraging. Within schools, increasing attention has been paid to the influence of the motivating style physical education teachers (PE) rely on, and how this affects motivation towards, and engagement in physical activity among children and adolescents.

The present grant proposal aims at investigating relationships between PE teachers’motivating style, youngsters’motivation, and their activity levels during and outside PE, hereby methodologically advancing previous research. This is by observing teachers’motivating style during real physical education lessons, and by objectively measuring youngsters’activity levels through movement devices (i.e. accelerometers) instead of relying on self-reports only. We furthermore investigate whether an optimized online application designed to observe and analyse videos of real PE lessons has potential to be used by teachers to self-analyze and effectively change their motivating style, to the benefits of youngsters’activity levels. The project is embedded in an international research program on motivational dynamics in physical education, which brings together researchers in motivational psychology, public health and sport pedagogy.