My PhD research focusses on the promotion of active and healthy lifestyles in children and reduce sedentary behaviour. This is to counteract the growing issue of obesity among children who spend much of their time sitting down at school and in their leisure time. I focus on the link between physical activity behvaiour and affective states, where affect drives physical activity/sedentary behaviour. Therefore, my research involves investigating the implicit mechanisms that may underlie this heightened sedentary behaviour through affective and motivational changes that impact self-regulatory behaviour in school-aged children. Eye-tracking and functional Near-Infrared Spectroscopy are used to inform the relationship between the changes in affective states and self-regulatory behaviour in relation to external physical activity cues.