Sebastien Chastin is a Professor of Health Behavior Dynamics in the School of Health and Life Sciences at Glasgow Caledonian University and in the Department of Movement and Sports Sciences at Ghent University. He received a BSc in Metrology and Applied Physics, a Masters in Applied Physics, a Masters in Rehabilitation Sciences, and a PhD in Non-linear Physics. He is a fellow of the Royal Statistical Society. Previously, he had posts at the British Antarctic Survey, Oxford, and Edinburgh University. His research focuses on the dynamics of health behavior related to aging, places, and systems. Understanding why, when, and how people decide to move or not is crucial to promoting healthy movement behavior and aging. He develops statistical and analytical techniques to extract information from body-worn sensors such as accelerometers that enable us to understand how humans accumulate physical activity, sedentary time, and sleep and how this changes over time.