Public health initiatives promoting physical activity (PA) are important to prevent and treat chronic diseases, especially in people with intellectual disabilities (ID) who face more health challenges. While pleasure experience during PA is recognized as crucial in general populations, it is remarkable that promotional efforts for people with ID often disregard the role of affect. This project aims to enhance our understanding of affect during PA among this population through two experimental studies. The first, using a counterbalanced between-subjects design, will explore whether people with ID have fundamentally distinct affective responses to PA, potentially experiencing less pleasure than a non-ID group. The second, using a cross-over 2x2 design with virtual reality, will examine the impact of two potentially powerful extrinsic strategies influencing affect during PA: social interaction and exposure to a green environment. Both experiments will utilize the same innovative and holistic test battery, combining EEG and facial expression analysis with questionnaires to overcome persistent shortcomings in existing measurement techniques for people with ID. This project will not only improve PA initiatives for people with ID by identifying 1) their affective responses to PA and 2) which extrinsic strategies could optimize affective experiences, but will also make a fundamental contribution to the research field through the implementation of a comprehensive affect-test battery.