Picking up the pace:the development of pacing behaviour during adolescence

How individuals distribute their effort during exercise (i.e. pacing) plays a key role in facilitating sports performance and exercise participation. In this thesis, we studied the development of pacing behaviour during adolescence. In a series of observational studies, the pacing behaviour of over 15,000 athletes (runners, swimmers and short-track speed skaters), aged 12-24, was studied using lap times recorded during competition. These studies demonstrated that in general the development of pacing behaviour 1) starts in late childhood, is most prominent during adolescence and becomes more gradual towards adulthood, 2) peaks at an earlier age in girls compared to boys, and 3) results in a distribution of effort that better fits the task characteristics (task duration) and the environment (presence of competitors). In a series of laboratory experiments, the various aspects of pacing were compared between groups of adolescents and adults performing cycling time trials. These studies revealed that the following capabilities develop during adolescence: 1) estimating the amount of effort required to compete an exercise task (e.g. estimating the time needed to complete a trial) 2) self-monitoring and adapting one’s effort expenditure during exercise (e.g. cycling at a set goal speed), and 3) using past experiences to inform one’s pacing strategy. Given that these capabilities are still developing during adolescence, children and young adolescents have the tendency to base their effort expenditure on signals from the social environment (e.g. by watching their competitors). The findings from this thesis offer a theoretical basis for the informed design of interventions and practical tools aimed at supporting the distribution of effort during exercise. These tools could be used not only to optimize the performance of athletes, but also to enable children and adolescents to enjoy engaging in physical activity and promote a healthy lifestyle