Characteristics of participating schools.

Research has shown that physical activity (PA) is important for health throughout the lifespan. Therefore, it is important that children develop the individual prerequisites that enable participation in PA throughout life. The theoretical concept physical literacy (PL) and the research field of PL has described such personal competences and traits. However, to promote PL among children and lifelong PA, there is a demand for more high-quality interventions to be developed and tested. When targeting children, schools are an important setting. Despite the possibility of promoting PL during PE lessons, few well-tested interventions have been developed. In this study, we therefore aim to context adapt and feasibility test an already existing and promising PL intervention to a Danish school context. The ADAPT and MRC guidelines were followed to adapt the Promoting Pupils Physical Literacy (3PL) intervention. Through workshops with stakeholders, the intervention was adapted to fit Danish 4th and 5th graders. Four Danish schools were recruited in a wait list design. The feasibility and acceptability of both the intervention and the effect study design will be investigated. To investigate the intervention, weekly questionnaires, observations, and interviews will be conducted during the intervention period. The feasibility of the effect study design will be investigated by collecting baseline and endline data on pupils’ PL and daily PA as well as parents’ socioeconomic status. Expected outcomes include a TIDieR checklist, a revised, feasible, and acceptable intervention, and an effect study design protocol. This will contribute to important steps in the direction of making PL interventions more accessible for practice. Valid testing of intervention effectiveness enables stakeholders to make informed decisions grounded in evidence. This will strengthen the possibilities of a successful outcome and for a PL intervention that is more accessible for practice, which is important for scale up.