As a scientist-practitioner working both in academia and in the field, Julien will provide an insight into his work to improve elite sport performance through adapted nutrition. The focus will be on endurance cycling and football, two very different sports requiring different nutritional recommendations. Julien will explain his work to understand the physiological demands of both sports in order to prepare individualised recommendations for athletes. Examples from the last Tour de France, Premier League and Ligue 1 football clubs will be presented. Julien will also explain how the results from his research are translated into practical solutions in the field and vice-versa or how questions from the field inform his research agenda. A focus will be made on carbohydrate periodisation strategies designed to upregulate the adaptation to training for better performances.